Sign in with
Sign up | Sign in
Your question

Please help with a PSU question - Urgent!

Tags:
  • Power Supplies
  • Components
Last response: in Components
Share
January 5, 2008 2:59:23 PM

Hi, I have a few questions about a power supply for you experts :) 

I bought an 8800GT. Currently I have a 430w power supply and obviously it's not enough. So I'm planning on buying a 550w power supply, but I'm on a tight budget.

I found a 550w PSU that's REALLY cheap...I was about to buy it, until I read the specs on their official website.

Ok so now for the questions...

1. Does it have enough 'pins' or whatever that people say you need for an 8800gt. I heard somewhere that you need 28 pins, volts, whatever it is lol. This is how much the PSU I'm planning to buy has(some of it is in Russian):

Power Supply Gembird CCC-PSU7-14 550W, ATX 2.2, CE, PFC, low noise, 14см. Fan, 20+4+4+6 pin, 2xSATA

ATX 24+4 pin или 20+4 pin (разборный 24-pin коннектор. 4-pin могут отстегиваться в случае необходимости), 6-pin разъем доп. питания (for video cards with more than 75w)


2. This is what I'm afraid of. Why is it so cheap? It says it's low noise and all...maybe because it's made in China? Will it break early or what?

Thanks.



More about : psu question urgent

a c 85 ) Power supply
January 5, 2008 3:23:08 PM

Full system specs, what psu

430 may be enough(My Q6600 @ 3.0, 6 hard drives and 8800 GTX takes under 300 watts to be honest...it all about the 12 volt rails)....

I would tend to watch out about PSU's that are too cheap. since they tend to cut on components.

As for what you need to run a 8800GT it just a PCI-E power connector....

Post back your specs and we will take it from there....
January 5, 2008 3:43:33 PM

Ok here they are:

Case: Midtower Swing Silver 430w glass window
Motherboard: Gigabyte i945P/UDMA133/Sata 2/DDR 667
Processor: BOX Pentium D 3.2 Ghz 2mb Cache - 800mhz
RAM: Kingston DDR2 1Gb @ 667mhz
Hard Disc: SATA 250 Gb @ 7200rpm
Video Card: Gigabyte GF 7600GT 256MB
Monitor: Samsung Syncmaster 193+

I know it's fishy that it's too cheap, but TBH I don't have enough money for a more expensive one. So...should I risk it?
Related resources
a b ) Power supply
January 5, 2008 4:15:17 PM

Hard to get any info on the PSU. Can you see what the amperage on the +12V rail is on any of the pictures. I can't seem to find any more info on that PSU. Been looking for 30 min. :( 
a c 85 ) Power supply
January 5, 2008 4:21:58 PM

Take a peak inside your system and see if you can read the info off the psu. get as much as you can.....or get the model of PSU you have now...

I would not risk it on a PSU you can not even get specs of

Hell you can be a 550watt psu with tons on 5 and 3.3 volt power and little 12. This could make it worse then what you have now....I have seen lots of 500 watt psus with less 12 volt power then many 250 watt psus
January 5, 2008 5:33:07 PM

Actually a good question, my 8800gt just came today and i currently have a scythe kamakiri 400watt psu. Will that run it with 20amps on both 12v lines or am i being overly ambitious. Sorry for the hijack.
a c 85 ) Power supply
January 5, 2008 6:24:44 PM

pookie, you need the total combined 12 volt output. This is not just adding them, it should be there somewhere....you machine is not power hungry so i am willing to bet its ok
a b ) Power supply
January 5, 2008 8:51:04 PM

Yeah I would bet either of the PSU's that you listed should be okay.
January 5, 2008 8:58:10 PM

I had just had a problem with not enough amps on my old PSU, even if it stated 500W on the +12v rail, it had problems holding those 12 v a long the single rail. The funny thing was that I didn't even have a lot of power eating components in my system.

This just shows how important it is to check after a PSU that has stable amps across the different rails and not just go blind on the total watts it puts out.

I got to borrow my friends 400W and this PSU keeps the amps very good across the rails and my problems of crashes etc are finally gone.

This just shows how important a good and reliable PSU is. Something I had to learn the hard way.
January 5, 2008 9:16:49 PM

The side of the psu is saying 245 watts on the 12v lines with 20 amps on 12v1 and 20amps on 12v2. I honestly have no idea how to calculate the combined wattage even though i read the psu sticky in the forum. Plus my girl got me the bfg oc2 8800gt which is recommending a 425watt psu minimum.
a c 85 ) Power supply
January 5, 2008 9:24:47 PM

245 is about 20 amps

The math is

Watts / volts = Amps
245 / 12 = 20.416666666666666666666666666666666666666666

I'd estimate your card even with a fair OC at about 8(Took the power of a 8800GTS 640 + a bit for good measure) amps
Your cpu should be around 65(if its an EE) to 89 watts(nonEE). Gonna say 7 amps(over doing it again)
So your still have some room for hard drives ect.

I'de run it, but keep an eye out for freezing and crashing....but also watch out as some crashing could be driver related...Keep an eye out for extra heat from the psu(They make heat, but if it gets real hot or loud it may be getting close to its limits...).
January 5, 2008 10:11:05 PM

cool thanks alot, imma love this tonight. Was waitin for this card cuz crysis was ok on my old x1950pro but this way i can run it on high at least at 1024.
January 6, 2008 3:41:02 AM

Oops nevermind I'll go with the Acbel one lol. Does IT have enough rails?

Thanks for all your help guys btw :) 
a c 85 ) Power supply
January 6, 2008 3:58:48 AM

They should both run your system without a problem. But they are also both rather limiting in information.
There are some images on the net to lead me to believe that the thermaltake has 140 watts on the 5 and 3.3 combined, This puts it in the 34 amp range.
Acbel has NO info, but i suspect its about the same.

The number of rails does not aways mean better. in fact most PSUs on the market use one large rail and virtual rails for over current protection. Its a safely feature and little more.
January 6, 2008 4:07:51 AM

Ok thanks nuke, one last question.

Turns out the 550w TT PSU isn't available. But there's a 500w one that IS available. Will the 500w version of the ThermalTake PSU be enough for the 8800gt? Or would I be pushing it?

Basically should I buy 500w now, or wait for the 550w?
a c 85 ) Power supply
January 6, 2008 5:03:11 AM

They do not list good specs for it(no combined listing). but i estimate it to be about 30 amps on the 12 volt rails....should run you fine...

Hell i half bet your current cpu could run you fine :) 

Just so you know i ran a Core2 E6600 X1900XT on a PSU with 18 amps on its 12 volt rails...

If you check my full system in more info under my name you will see it all draws under 350 watts....Its quality not quantity of power...
January 6, 2008 5:22:20 AM

I'd rather not risk it :) .

Yeah so I might get the TT 500w or the Acbel 550w...

Hm but the Acbel one seems fishy, might not have enough on the 12 volt rails. Got the info from the official site:

http://www.acbel.com/PDF/P_PC/ps2_550W_gold.pdf

Where it says 'output current capacity'.

Apparently it has 3 12v rails but neither of them have enough amps? Am I correct?
January 6, 2008 5:23:45 AM

Never ever waste money on a cheap PSU, when it comes to PSU's you get what you pay for.
I would never buy anything on the PSU list below tier 2. It's just a waste of money, and can kill a system if it dies.

http://www.xtremesystems.org/forums/showthread.php?t=10...

I like to stay with the tier one PSU's
January 6, 2008 5:55:53 AM

Thermaltake TR2 PSUs are low power units, and considering the 430W only supplies 18A (single rail), I doubt the 500W supplies more than 25A. They are better than many OEM PSUs in terms of component quality, but for a high end system they aren't a good choice. You'd be better off getting an Antec Earthwatts if possible, this PSU probably costs more than it's worth.

@Nukemaster: I ran the TR2 430W (with 18A) and it couldn't power my X1950 pro and 3700 sandy. What PSU were you using for that system?
a c 85 ) Power supply
January 6, 2008 6:05:00 AM

d3lit3 said:
I'd rather not risk it :) .

Yeah so I might get the TT 500w or the Acbel 550w...

Hm but the Acbel one seems fishy, might not have enough on the 12 volt rails. Got the info from the official site:

http://www.acbel.com/PDF/P_PC/ps2_550W_gold.pdf

Where it says 'output current capacity'.

Apparently it has 3 12v rails but neither of them have enough amps? Am I correct?

It shows 12 22 and 14.....thats plenty, but they do not say how much it can put out at once....for sure you can not take 12 22 and 14 all at the same time.... because that would be 576watts and thats not even including the 3.3 and 5

Thats the pain with poor labels. It nice when they show the total 12 to make it easy to see.....


+ 12(1) , +12(2) MAX 360....perfect 360 / 12 = 30 amps
Perfect No guessing its labeled right....


Under +12(1) and + 12(2) you see the max of 432. 432 / 12 = 36 amps
Perfect No BS here


In the fine print 12 volt rail 50 amps... This is a example of not adding the rails...if the psu was 20c it COULD get more, but pc's do not tend to be 20c


+12 1 & +12 2 MAX 348. 348 / 12 = 29 amps

See a trend here.....Thermal take and Acbel do not say the total.....its clear the acble offering can not put out all its rails at full load....more like 25-30 combined....will that run you system.....I say yes....

You still did not list your 430watt one.... Just curious
a c 85 ) Power supply
January 6, 2008 6:05:45 AM

randomizer said:
Thermaltake TR2 PSUs are low power units, and considering the 430W only supplies 18A (single rail), I doubt the 500W supplies more than 25A. They are better than many OEM PSUs in terms of component quality, but for a high end system they aren't a good choice. You'd be better off getting an Antec Earthwatts if possible, this PSU probably costs more than it's worth.

@Nukemaster: I ran the TR2 430W (with 18A) and it couldn't power my X1950 pro and 3700 sandy. What PSU were you using for that system?

Antec TP380s
Prime95 and Crysis looping its bench
January 6, 2008 6:10:14 AM

Goes to show how good the TR2s are :/ 
January 6, 2008 6:19:53 AM

Ok Nuke you asked for 'em :) 

Here's the PSU I currently have;

AC INPUT: 115/230V 8/4A

Frequency: 47-63 Hz

DC OUTPUT:

+3.3V +5V +12V -5V -12V +5VSB
28A 30A 18A 0.5A 08.A 2.0A

18 amps isn't enough...

So which one should I get? The Thermal 550w or the Acbel 550w?
a b ) Power supply
January 6, 2008 6:44:14 AM

My first gut instinct is the Acbel, but I don't know there history/background. I know that the TT's TR2's are generally weak, but not sure which way you should go. Is there a website that we can look at that we can help you find a more reputable PSU from?
January 6, 2008 7:01:00 AM

What's your budget? (in the currencies on the sites please :) )
January 6, 2008 8:21:19 AM

I can go up to 90$ or in Rubles 2500p.
January 6, 2008 11:13:01 AM

Don't get cheap PSU. Some may explode and it is too risky.

Edited: I would not get either one. They are simply too old
and too emphasize on +3.3V and +5V, and the output of
+12V rails would not be enough for your 8800GT. I was getting
the wrong model...
January 6, 2008 10:26:45 PM

Here you go, nicely in budget:

http://www.arkis.ru/ru/catalog/complect/case_power/p295...

I am not sure what the voltages are where you live, but the ATX-450PA can run 115V and 230/240V inputs. The ATX-450PAF can only do 230/240V according to the manufacturers site, so I would avoid this one if you need 115V input voltage.
January 7, 2008 10:23:35 AM

Thanks randomizer. But for some reason it's really cheap with only 450w. Are you sure it won't explode with an 8800GT :) ?

Btw the voltages where I'm living is 220V.
January 7, 2008 9:31:14 PM

But it's where most of that 450W is that matters. The total output for this PSU could be 2kW yet if none of that enormous amount of extra power is on the +12V rails then it is not one bit better. In this case, 360W (30A) is available on the 12V rails, making it quite powerful for a 450W unit. Assuming all 360W was being used, only 90W would be left to split between the +5V and +3.3V rails, but that is more than enough since very little uses those rails any more. It is cheap because it doesn't have the fancy LEDs or anodized coating of many of the more expensive units, but it still uses decent quality components because it is made by Fortron Source (FSP). Another example of this is the Antec Earthwatts, which are also high quality, but they don't have the looks or the pricetag of many other brands either. The only downside with these particular FSP PSUs is they aren't incredibly efficient (>70%), meaning they will pull a bit more power from the wall socket than others of 80% or greater efficiency (such as the Earthwatts). Unless you run your PC 24/7 under heavy load, it won't make a big difference.
a b ) Power supply
January 8, 2008 1:09:36 AM

Totally agree with Randomizer on this one. Get the FSP PSU and be done with it. You won't look back after you get it. :) 
February 20, 2008 3:33:01 PM

I don't know what you spent on the 8800, but cutting corners when it come to PSU is not wise. The PSU is what will insure a solid reliable operation of your computer. Cutting corners can lead to strange happenings and damage to equipment in the computer.

As to this multi rail crap, a single rail will work far better as will a very solid, expensive PSU that will last.

I have had two Antec failures so far and now run PCP&C, I also oversize the PSU. A cheap power supply means you now have a computer that is worth just about as much as the power supply.

Evan
February 20, 2008 3:35:32 PM

I don't know what country you are in, but if it is the US you can go to New Egg and get a PCP&C 750 Watt on sale for about 150.00 US. You will no longer have need of a lengthy discussion over what power supply to buy or whether it will work.

Evan
February 20, 2008 3:40:36 PM

New Egg has a 610 Watt PCP&C for 120.00 + shipping.

Evan
!