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Trouble in SLI ville

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a b ) Power supply
August 3, 2007 3:53:48 AM

This is just a little warning for all you guys that are asking what P/S do I need for my build, in this day and time especially if SLI or Crossfire is in your build plans or in your future possibilities, underpowering an SLI or Crossfire setup could cost you your Video card or cards.

I'm not going into my story of whats just happened to me [Its too long], but I'm stressing to you that in the old days the power supply was the last thing on the build list, but it needs to be a first and primary decision in your build today, having the proper amperage per rail is a major factor today, and actually you need more than whats reccommended to be on the safe side.

You need to find out what all your components draw amp wise especially your video cards, and get a power supply thats more than capable of handling the load, my failure was not figuring in that OCIng increased the main load draw so thats also a consideration to add into the decision for whatever P/S you decide to get.

Heres a couple of links to help you decide what P/S you may need for an SLI or Crossfire setup, however do your own research and choose a P/S that delivers the required 12V rail amperage for each card you use.

http://www.slizone.com/object/slizone_build_psu.html

http://forums.nvidia.com/lofiversion/index.php?t39313.html

http://ati.amd.com/technology/crossfire/buildyourown2.html

More about : trouble sli ville

a b ) Power supply
August 4, 2007 11:33:33 AM

bump
a b ) Power supply
August 4, 2007 1:25:58 PM

Yes, and quality of PS matters a lot too. I have a PS that is decent and probably can put out its rated 550W, but it had too big of voltage drops. I think it made my comp a little unstable. Now I have a graphics power supply to take some stress off of it and everything's great.
Related resources
a b ) Power supply
August 4, 2007 2:17:59 PM

Nice OC on the FX-60, I got mine up to 3g but with watercooling, then pump failure happened and I went back to air and 2.81g same as you, I was able to successfully run a 15X multi on the FX-60 @ 1.56v = 3,013mhz @ 28c W/Cing rock solid.

Wrote it all down just in case I went back to running the FX-60 to save me some time, never tried it on air cause I went back to my FX-57 on air 15x @ 3,018mhz on air, and the wife inherited the FX-60, my last years Christmas present from her, I'd say she racked up wouldn't you.
a b ) Power supply
August 4, 2007 10:57:11 PM

This is the best OC I could pull off because my ram doesn't like to OC, the comp wouldn't post at 3GHz, and the 1/2 multis (14.5, etc.) really screwed things up (SLI failed, ram ran at the wrong speeds, etc.) I wanted a low voltage "safe" OC, and really this comp was fast enough w/o OC.
a b ) Power supply
August 4, 2007 11:45:38 PM

@ 4ryan6 Hi mate, sorry to read that you have had probs, not the release of the magical blue smoke I hope. :??: 
a b ) Power supply
August 5, 2007 1:40:04 AM

Mousemonkey said:
@ 4ryan6 Hi mate, sorry to read that you have had probs, not the release of the magical blue smoke I hope. :??: 



Well at this point I'm not exactly sure how far the damage goes, but its because of not having enough amperage to push 2 OCd 7800GTX, this has and is a learning process for me.

To make a long story short, its my fault, I first ordered my build with just one 7800 and chose the P/S I thought would be adequate to add the 2nd 7800 later, to be quite honest it was and still is reccommended by the nvidia website, but is far from being what I really needed.

I guess nvidia decided if they got it up and running with a certain P/S, it would be OK even though it didn't have the amperage needed to long term survive, this build was back in Feb of 2006 so a lot of knowledge has come down the pipe since then regarding 12v rail amperage, and others discovering some of the suggested P/Ss weren't up to the task after all.

I'm not blaming nvidia for my short comings, I was so excited at the time of the build, I was getting to put together a dream machine from a hefty income tax return, I could've bought any P/S on the market and thought I was getting exactly what I needed, but I was wrong.

So now my impatience could cost me more than I ever even considered, so I've ordered a P/S that could probably crank my truck and when its installed, either all the problems will disappear or whatever is damaged will become completely obvious.

So thats where I'm presently at Al, and hoping for the best outcome. Ry
a b ) Power supply
August 5, 2007 11:51:55 AM

EXT64 said:
This is the best OC I could pull off because my ram doesn't like to OC, the comp wouldn't post at 3GHz, and the 1/2 multis (14.5, etc.) really screwed things up (SLI failed, ram ran at the wrong speeds, etc.) I wanted a low voltage "safe" OC, and really this comp was fast enough w/o OC.



Did you get a heatpipe cooler with the FX60, retail, or did you get the OEM ?

Just asked because the retail FX60 heatpipe cooler can handle more heat than you may realize as long as your case has good airflow.

Quote:
This is the best OC I could pull off because my ram doesn't like to OC


2GB Corsair XMS 400MHz 2-3-3-6-1T Would need the voltage increased on the dimm slots to get it to do what you want, but that RAM will OC.

Quote:
I wanted a low voltage "safe" OC


FX-60 @ 2.81GHz (1.375V, 90nm, 14x multi) What are your temps? Actually to be running a 14X on the FX60 the voltage is a little on the low side 1.4v should be better, I'm surprised you're not having random freezes and unexplained computer funkiness.

[Computer Funkiness, a ryanism. :lol:  ]

Quote:
(SLI failed, ram ran at the wrong speeds, etc.)
What cards were you running in SLI at the time?

I also had some SLI trouble with the FX60 but it wasn't because of the OC, it was under powered video cards, and not dedicating a core for a specific task.


August 5, 2007 12:26:00 PM

750W is ample for anything apart from quadcores with ultras, eg, i can run my system on my old thermaltake toughpower 750W if i clock it back to stock speeds, but at stock speeds i loose 30% performance, so the 60% power increase from the overclock i just chose to do the smart thing, buy a 1200W psu and not give a **** about heat or power usage
a b ) Power supply
August 5, 2007 2:03:08 PM

The cooler on my FX-60 is an Ultra X-Wind, which is really a design stolen/bought from Zalman. It is a giant mushroom shaped copper fan that keeps temps nice and low. As for airflow, I took the side of my case off and set a 8 inch fan blowing on it, so airflow isn't a problem.

To be honest about the OC, I blame it on the RAM, but I think it may actually be the motherboard. Its a long story, but here it is...

I originally had 1 GB (2x512) of Corsair XMS. Overclocked great, 2-2-2-5-1T @ 430MHz. It wasn't quite enough for some of the new games, so I decided to add another Gig of the same stuff. This would have been fine, but at the time I didn't know that four sticks couldn't run 1T command rate. It crashed, I went back to 1 Gig and realized the problem, but now my second 6800GT would only register and allow SLI sometimes (as time passed, almost never.) So I wrote to Asus, they said send it in, and two weeks later I got the same board back. Miraculously, SLI worked! I was hoping that they would replace the board, but at the time I was just happy my comp worked.

Actually, it is one of the last things not replaced on my comp:

3800+ => FX-60
A8N-SLI Deluxe
1 GB Ultra Ram (2x512) => 1 GB Corsair XMS (2x512) => 2 GB Corsair XMS (2x1GB)
6800GT => 2x6800GT => 2900XT
JPC 485W PS => Ultra 550W PS => Ultra 550W + Thermaltake 250W Graphics power supply
250GB Sata HD => 250GB Sata + 30GB IDE (the 250 corrupted, but after reformat was fine. I again blame the MB)

So I have a feeling that the MB may be the culprit, it is over two years old and has had a rough life.

OK, onward,

Temps on my current FX-60 OC are good (I think). I can't remeber the exacts right now, but idle is just a few degrees above room (30C, maybe). As for max, with both cores loaded it tops at 50-55C (thats with a hot 2900 below it!)

I originally wanted no voltage increases so it lasted a long time, so my first OC was 2.81 GHz @ 1.35 (stock) voltage. That I discovered was a little unstable, but 1.375V seems to have remedied that.

I think that answers all of the questions. Whew, thats the longest one I've wrote in a long time, maybe ever.
a b ) Power supply
August 5, 2007 3:14:43 PM

That Ultra X-Wind seems to be doing a pretty good job controlling your temps, I just bit the bullet and ordered a Tuniq Tower, I want to OC my FX57 as far as I can push it on air, when I was W/Cing I had her up to 3,214 with a 16x multi, stable.

Also ordered a Silverstone OP1000 P/S single 12v rail @ 80a to make sure my video cards have all the power they need cause its OCing time my friend, I'm going to see just what I can get out of this machine on air.

Theres one finicky thing O/Cing both the FX57 and the FX60 the RAM clock has to be 200mhz locked in when increasing the multi or it'll crash everytime, even 201 and its down for the count, and some M/Bs like to auto set the FSB to 201 to 203 for an additional performance boost, but with the multis unlocked on the 57 & 60, that pushes the HT too far for those speeds and instant crash.

Lock the memory clock in @ 200mhz and the RAM funky goes away.

Theres kinda like a perfect operating window with the 57 and the 60 when you increase the multiplier and if you're in that window its rock solid, its harder to get the 60 in the window than the 57 because of the heat generated from the 2nd core.

FYI I'm just sharing learned information with you since I saw you are running an FX60, and I have one also, I'm not trying to convince you to do anything here so please don't take it that way. OK

This thread was started because of an under powered P/S and I really just hope when I get the OP1000 that theres no damage to any of the hardware ! Keeping fingers crossed on that one. Ryan
a b ) Power supply
August 5, 2007 5:47:59 PM

I know you're not trying to make me do anything, and its good to know that it's not just my comp that is a finicky OCer. For now it is plenty fast enough, so I will worry about a better OC once this comp is more obsolete and I need more speed.

And good luck with your system, I've never had a PS go out (only cause minor instability), so I hope everything is OK.
a b ) Power supply
August 5, 2007 6:04:31 PM

Thanks
a b ) Power supply
August 10, 2007 6:57:36 PM

Update, seems both my video cards are OK to run in a single setup, however [DFI M/B jumpered in SLI], it won't even boot into Windows, take it out of SLI no problems.

Both of the single video cards exibited a little jerkiness playing FarCry in 1920 X 1200 resolution, but since installing the new P/S that problem disappeared completely, thanks to a friend I have another SLI M/B to change out and test to conirm whether the SLI problem is M/B or Video related.

I am relieved I haven't toasted either of the video cards, I can get by without SLI if I have to, but if you're running SLI you know it kinda spoils you a little.
August 10, 2007 7:24:23 PM

If you guys spend all this money to overclock, and on 1200 watt psu (rammedstein), why are you running FX anythings and not cores ?!

4ryan6, it's not Nvidia's fault on the recommendation either, they don't figure you overclocking when they recommend a powersupply either, as their is no way to know what you'd do to your system.
a c 92 ) Power supply
August 10, 2007 7:28:50 PM

Sorry if I missed where you said it, but what PSU died on you?

I would also like to take this time to remind people that you need to keep your computer clean. You can't just buy a computer, plug it in, and expect it to run forever. (this is even more true if you have any higher end parts.) Dust will get in the heatsink, causing a raise in temps. If it runs to hot, it WILL die. (it being CPU, GPU, PSU, etc) I clean out my machines at least twice a year, whenever we switch on/off of daylight savings. Start at the top of you machine, and get all the dust out. Toothbrushes work great at getting the dust out of the heatsinks. (don't forget to remove the fan over the heatsink, and clean the fan blades while your at it.) I feel comfortable enough to open the PSU and clean it also, though this isn't for everyone. Seeing as you'll void the warranty if you do open it, you might want to just blow out what you can until your warranty is over. The same goes for store bought computers, if you open the side of the case, your warranty is gone.

Proper cooling = less heat = longer life span.
a b ) Power supply
August 10, 2007 7:35:00 PM

@ RoyalCrown

Quote:
4ryan6, it's not Nvidia's fault on the recommendation either, they don't figure you overclocking when they recommend a powersupply either, as their is no way to know what you'd do to your system.


Its Nvidias fault when they reccommend a P/S to run in SLI as being sufficient for a stock setup thats underpowered on its 12v rail or rails, when their stock listed video card draws more power than the suggested P/S delivers.

Yes OCing increases the draw but Nvidia has reccommended some P/Ss that aren't sufficient for their stock video cards amp draw!
a b ) Power supply
August 10, 2007 7:55:46 PM

@ 4745454b

Quote:
Sorry if I missed where you said it, but what PSU died on you?


The P/S didn't fail it continued delivering its underpowered amperage until the combined load took its toll elsewhere, maybe thats a testament to the durability of the Fortron FX700-GLN, the same P/S reccommended by Nvidia to run 2 7800GTX in SLI, the M/B is whats failed in SLI, the P/S still works.

The combined draw of both 7800GTXs and the M/B were more than the P/S was capable of delivering, for the hardware to operate at its maximum effiecency it needs the available amperage required, what surprises me is Nvidia reccommending an under powered P/S in the first place.

You can check this out for yourself with the above links, and Newegging the Fortrons spec label.
August 11, 2007 1:26:28 AM

I was not attacking you 4ryan6, I just say it is odd. All the 7800gtx cards I could find, even 512 mb draw around 80 watts apeice, so 15 amps max on 4 12 volt rails should be plenty more than enough. that is only 160 watts total or about 7 amps each under load.

Seems like that would be more of a motherboard problem with the PCIe slots, or a prob with the power supply, unless the cards are drawing more than 80 amps each. Even if they draw almost twice that, you'd be okay going by the sticker, but that depends on how truthful it is.


You are the one said you were overclocking, not me anyhow.
a b ) Power supply
August 11, 2007 6:49:12 AM

royalcrown said:
I was not attacking you 4ryan6, I just say it is odd. All the 7800gtx cards I could find, even 512 mb draw around 80 watts apeice, so 15 amps max on 4 12 volt rails should be plenty more than enough. that is only 160 watts total or about 7 amps each under load.

Seems like that would be more of a motherboard problem with the PCIe slots, or a prob with the power supply, unless the cards are drawing more than 80 amps each. Even if they draw almost twice that, you'd be okay going by the sticker, but that depends on how truthful it is.


You are the one said you were overclocking, not me anyhow.



Trying to discover the true problem has been a constant, change this, try that, process, but I've discovered just how important the proper P/S really is, and if the video card draws 26A Stock, you'd better give it a P/S that supplies more than 26A per 12V rail per video card or get ready for trouble.

Hopefully this thread is to keep others from making the same mistake I did, I did a lot of research trying to find solid information on amperage draw of my 7800GTX 256mb, I've used 3 different brand M/Bs an ASUS, and EpoX, and this present DFI, the ASUS M/B died after 3 months, the EpoX never died but acted extremely weird in SLI, and the DFI now refuses to boot set in SLI mode.

The Fortron P/S outputs 15A on its 4 12v rails, it was used on all 3 M/Bs, I didn't relate the P/S to the ASUS M/B failure at first, as far as the M/B I thought I'd gotten a lemon, and the DFI M/B seemed to be OK in the beginning until it wouldn't play a game when the 3D kicked in, in SLI.

I picked up a 800W BFG P/S [also reccommended by Nvidia] outputs 20A per 4 12V rail since I had discovered the cooling fan itself on the 7800GTX pulls 18A it was stamped on the fan motor, was able to play in 3D with SLI and at first I thought the problem was solved until it shutdown period, so I looked for some absolute total amperage draw information and found the chart at nvidia on the amperage draw [the second link above at the top of the thread], and discovered the 7800GTX 256 and 512 both pull 26A stock.

Overclocked it would have been even more, so even the BFG was underpowered feeding the video card as a single card much less in SLI, and a single 7800 GTX wouldn't run at one point with the Fortron, but would run with the BFG if I dropped the GTX back to stock settings.

So I'm now running a Silverstone OP1000W 80A single 12V rail, the card in single mode 7800GTX runs flawlessly all the weirdness the card exibited is gone completely, the DFI will not even boot into SLI, so it may have somehow gotten damaged.

I beleive all this is attributed to the insufficient amperage of the Fortron P/S, however its not Fortrons fault I bought that particular P/S, I could've bought any P/S on the market at the time, Nvidia needs to update its reccommendations for SLI, a certain P/S may start out running SLI and things seem OK, but its the long term when things start failing that everyone needs to be concerned about.



August 11, 2007 7:20:13 AM

it should be .18 amps, the amp rating only pertain to the fan on the card and all the cards I found draw about 80 wats, so I divided 80 wats by 12 volts and that gives you a rough total of the amps drawn through the pci slot and the connector total. That is only 7 amps roughly and this is off Leadtek's site and a few others.

It could be something with your board or when you overclock, you draw more amps through your boards VRM (voltage regulator module) then it can handle, now I dunno why it wouldn't work if it is stock though.

Check out some of the latest 8800 gtx cards, even in those systems, they only draw a bit over 300 amps with 1 card, you should had a boatload left unless you have 8 hard drives or something.

http://enthusiast.hardocp.com/article.html?art=MTMyNCwy... zaWFzdA==

and here

http://www.tomshardware.com/2005/06/22/24_pipelines_of_...
August 11, 2007 7:31:03 AM

4Ryan6 said:

I picked up a 800W BFG P/S [also reccommended by Nvidia] outputs 20A per 4 12V rail since I had discovered the cooling fan itself on the 7800GTX pulls 18A it was stamped on the fan motor, was able to play in 3D with SLI and at first I thought the problem was solved until it shutdown period, so I looked for some absolute total amperage draw information and found the chart at nvidia on the amperage draw [the second link above at the top of the thread], and discovered the 7800GTX 256 and 512 both pull 26A stock.


18 amps on a cooling fan? (216w 12vdc, 90w 5vdc) WTF is cooling your cooler? I've got a 120mm 12VDC delta fan that pushes 105+ CFM that is rated at 0.68A that’s only 8.16w. I think you misread that label.
August 11, 2007 7:38:59 AM

royalcrown said:
it should be .18 amps, the amp rating only pertain to the fan on the card and all the cards I found draw about 80 wats, so I divided 80 wats by 12 volts and that gives you a rough total of the amps drawn through the pci slot and the connector total. That is only 7 amps roughly and this is off Leadtek's site and a few others.

It could be something with your board or when you overclock, you draw more amps through your boards VRM (voltage regulator module) then it can handle, now I dunno why it wouldn't work if it is stock though.

Check out some of the latest 8800 gtx cards, even in those systems, they only draw a bit over 300 amps with 1 card, you should had a boatload left unless you have 8 hard drives or something.

http://enthusiast.hardocp.com/article.html?art=MTMyNCwy... zaWFzdA==

and here

http://www.tomshardware.com/2005/06/22/24_pipelines_of_...

Don't you mean 300w (25A @12vdc)? You would have to run your GPU with a 4000w PSU at 300 amps. :lol: 
August 11, 2007 8:04:49 AM

@Gh0stDrag0 n:

Yeah, 300 amps is what the 5600 FXes draw, sorry...lol
August 11, 2007 8:18:14 AM

hi guys i just wanted to ask u this one question, this might be off topic but will help me so much. will pc power & cooling silencer 750 crossfire edition support 2900xt in crossfire. i mean by wattage and amps. hope to hear from u guys soon
a b ) Power supply
August 12, 2007 2:39:25 AM

Gh0stDrag0n said:
18 amps on a cooling fan? (216w 12vdc, 90w 5vdc) WTF is cooling your cooler? I've got a 120mm 12VDC delta fan that pushes 105+ CFM that is rated at 0.68A that’s only 8.16w. I think you misread that label.



ROFL My Bad! There is a decimal point before the .18A

At the top of this thread the second link, do you think the total 26AMP draw is accurate for the 7800GTX? The guy doesn't link where he got his information and personally I just want to find out for sure what the actual AMP drain actually is for the 7800GTX.
a b ) Power supply
August 12, 2007 3:58:26 AM

@ Royal Crown

The first article is 2 yrs old and the second is 1 and 1/4th yr old, my entire point is past reccomendations have to be inaccurate, there were corrections even in the articles their statements weren't completely accurate, I am not the only person thats ran into this power supply inadequacy problem.

So its a fact its happening, those articles don't address the 12V amp draw which seems to be the killing factor, wattage really doesn't matter if the amperage isn't there on the 12V rail, if you have 10,000 watts [exageration]but your 12V rails are pushing 1A its not going to properly run these new video cards.

In the same respect if a 400W P/S was pushing say 70A on a single 12V rail, it should be sufficient, but you won't find one out there, and if you do let me know.

Presently my problem is solved they have 1000Ws to suck up all they need and a 80A 12V rail, so they'll either run like they're supposed to or blow up, either way its time to play.

By the way, your avatar makes me thirsty!

Down an RC for me, all I have is Coke right now!
August 12, 2007 5:10:25 AM

True, but if you divide your watts by 12 volts, you'll get the amps. I am glad stuff is working though.
August 12, 2007 5:49:32 AM

They won't blow because amps can't get pushed into the cards from the powersupply, a device can only draw exactly what it can use for amps. Now voltage can get "pushed", it is opposite. I went for electronics engineering so no BS :) . I happen to love coke too, but when burned out..RC rocks also, just not that P word.
August 12, 2007 5:57:26 AM

4Ryan6 said:
@ Royal Crown

The first article is 2 yrs old and the second is 1 and 1/4th yr old, my entire point is past reccomendations have to be inaccurate, there were corrections even in the articles their statements weren't completely accurate, I am not the only person thats ran into this power supply inadequacy problem.

So its a fact its happening, those articles don't address the 12V amp draw which seems to be the killing factor, wattage really doesn't matter if the amperage isn't there on the 12V rail, if you have 10,000 watts [exageration]but your 12V rails are pushing 1A its not going to properly run these new video cards.

In the same respect if a 400W P/S was pushing say 70A on a single 12V rail, it should be sufficient, but you won't find one out there, and if you do let me know.

Presently my problem is solved they have 1000Ws to suck up all they need and a 80A 12V rail, so they'll either run like they're supposed to or blow up, either way its time to play.

By the way, your avatar makes me thirsty!

Down an RC for me, all I have is Coke right now!


Not to be picky here, but if a 400w psu could put out 70 A on a single 12 VDC rail, then it wouldn't be a 400w PSU, would it?

And you better check the specs of your new PSU REAL close... If you use 80 A of a 1000W PSU on the 12v rail, that leaves a grand total of 40 W for all of the rest of the PSU's various rails combined... Ok, I AM picky.
a b ) Power supply
August 12, 2007 6:16:37 AM

Hello Ry, glad to read you're getting the issues sorted out, sounds like one meaty PSU you've got for yourself. Is the mobo still suspect? or have you sorted that as well?
a b ) Power supply
August 12, 2007 6:04:00 PM

Mousemonkey said:
Hello Ry, glad to read you're getting the issues sorted out, sounds like one meaty PSU you've got for yourself. Is the mobo still suspect? or have you sorted that as well?


Hi Al, The M/B will no longer run the cards in SLI, it won't even boot into Windows when its jumpered for SLI mode, [A Bank of jumper blocks to run SLI, Its a DFI setup], each card by itself works just fine.

I have a backup M/B to swap out and test the SLI on to see if the problem is M/B or video card related but after all the P/S swapping and testing I've done in the last 3 weeks, I'm testing and swapping burnt out!

I'm just glad the video cards are OK and I'm enjoying playing some FarCry and F.E.A.R. right now.

Even with a single 7800GTX I can max all the graphics settings in FarCry and play @ 1920 X 1200 all day smooth as glass, so I really don't need the SLI right now anyway.

The meaty P/S is really future proofing for when the opportunity arrives to upgrade, since the P/S needed to be replaced anyway, just getting by with the present situation and possibly buying another down the road when upgrading becomes doable, seemed kinda out of the question to me!

To be quite honest with you Al, I'm questioning why I started this thread in the first place, it was originally to get others attention to take their P/S build choices a lot more serious than, "Oh Yeah, I also need a P/S !"

The point I've been trying to make is past articles and P/S reccomendations haven't stood the test of time, and others today are claiming more power draw than was originally stated, but where are they getting their information and is their information accurate?

The second link at the top of this thread states a 7800GTX amp draw for a stock card is 26W, if his information is accurate and swapping out these P/Ss seems to back up his statements, then a lot of us made build decisions based on inaccurate information.

I'm not concerned with how a P/S works or knowing all the wattage amperage calculating simple math crap I'm being handed, just that its powerful enough to do what I need it to do for the basic life of my computer, and though eventually everything does have an end and have to be replaced for failure reasons, does the under powered P/S cause failures in other components?

With my circumstances and what I've seen so far I'd have to say yes to that, but proving it seems to be more of a challenge for those that want solid facts and think their answers are the only right ones.

Seeing as how on a standard M/B the PCI-E is limited to a certain amount of wattage, how does that change when a M/B manufacturer such as DFI adds a specific M/B connection to add more power to the SLI hardware, that does change things doesn't it?

If an additional voltage output is required from the power supply its an additional drain on the P/S, and thats added to the total P/S load. Right?

Now we know what happens to electronic components when they're fed too much power over time, but what happens when they're under powered over time, if they're out of their spec'd sweet spot, what does that do to them? Obviously they won't work at their optimum capability, but over time will they just stop working?

Al, you do realize I'm making a conversation of logic with you here and using you to make a point I've been trying to make since this thread started, you are my friend and I'm not questioning you, I just want to make that clear before I proceed.

My logic here is plain, it either works or it doesn't, I have a working 700W P/S delivering 15A per 4 12V rails.

Two ASUS M/B failures, one EpoX M/B displaying weirdness in SLI but did not fail, one DFI M/B that has seemingly failed to be able to run SLI, all the M/Bs were run from the same still working P/S.

I had never considered the P/S as being the problem all along, since for one it was still working and two was recommended by Nvidia for an SLI setup with 2 7800GTX video cards, until the video cards died going into 3D mode and all this trouble began.

Then the swapping out and testing began to try and discover what the heck had happened, leading me to the conclusion the under powered P/S was the problem all along, and possibly contributed to the failure of the first ASUS M/B!

Can I prove that beyond a shadow of a doubt?

No I cannot!

This thread could best be served by input from others in the same boat, not those standing on the shore tossing in their opinions having not experienced any of the said problems and probably aren't even running SLI in the first place.

Swapping P/Ss I did discover afterwards it took 20A per 12V rail just to run a single 7800GTX with stock card settings and it was a little shaky in its performance, but did not freeze up or stop rendering, but would not run SLI however I believe that to be a M/B problem now.

The present P/S solution runs the 7800GTX flawlessly, as a matter of fact individually they seem like brand new cards, I guess they've been starved for power all this time, the M/B though it won't run in SLI is working as a single setup just fine also.

So it boils down to simply getting my second wind and swapping out the M/B to hopefully regain SLI capability, or upgrading my 2nd machine to gaming status! Not! Just kidding, I didn't pay for the SLI for nothing!

Thanks for being a sounding board Al! You're a good friend! Ry

August 12, 2007 11:20:05 PM

Usually under powering a component won't damage it, refrigerators yes, IC's no. I am glad your up and running, I am gointg to try VISTA, so I might break MY machine next...lol. Good luck on the swap ! Keep your particle gun loaded and clones microwaving :D 
!