Hi

My system builder and I are putting together a 790i machine with 2 9800 GX2's, and we are having a nightmare trying to find a stable configuration.

We've tried both the Asus Striker II Extreme and EVGA 790i boards, different power-supplies, swapping memory etc., but are unable to get a system which gets much beyond booting without blue-screening. Spec is:

Intel QX9770
Asus Striker Extreme II / EVGA 790i (we've tried a couple of each)
2x XFX 9800 GX2
4GB Corsair DDR 3 RAM
Various DVD drives (we've tried a bunch)
2x 1GB Samsung SATA hard drives (non RAID)
Windows Vista 64bit
Air cooling


With one graphics card we can get the system stable. If we disconnect all the SATA DVD drives we can get it stable. Even without overclocking, and with the graphics cards underclocked, we canot get the full config to run reliably - blue-screens pretty much all the time. Temperatures are not the problem - very low when idle and pretty low under load.

Has anyone built a stable 790i SLI rig, or know of a spec' which is supposed to be stable, because we're pretty much out of ideas?

Many thanks for any help

Jules

780i boards dont play nice with the new quads. Its a known issue since Nvidia wont licensw sli to Intel they changed something in the chips on the new quads to screw with 780i chipsets.

I guess the same applies for 790i .... ?

I kind of see the thinking, but seems weird for Intel to sabotage their own market like that, just because somebody won't license something.

Thanks for the response.

Jules

I could be wrong, but I have read about this.


What is your Power supply. Maybe you just dont got enough power for that beast.

Since it works good with one card it could be a power issue.

You probably need a good 1000watt +

Try loading XP rather than Vista and see if you get more stable results.

THE BEAST.
It is hungry.
Feed it.

No, thats why we have a 790i, nVidia had to rush out the 790i so they would have 45nm quad support.

Yea you dont specify, what wattage and brand PSUs have you tryed

Hey Trailerman,

I am currently using an EVGA 790i Ultra board rock solid, heres my specs >>


Intel Core 2 Quad Q6600 @ 3.4 GHZ (overclocked) @ 1.35v

Thermaltake V1 Cpu Cooler (modified with (2) 120mm fans)

(4)GB Corsair XMS3 DDR3 memory (overclocked to 1200 MHZ) @ 1.7v

- - - Ram cooled by a Corsair Dominator ram cooler.

EVGA 790i Ultra Motherboard, FSB @ 1511 @ 1.4v Bios: ver P03

(2) BFG 8800 GT in SLI configuration (overclocked to 700/1000/1600)

(1) Creative Labs Fatality X-FI Extreme sound card

(4) Sata II Seagate 250 Gb HDD running in Raid '0' for performance striping.
( Equals a (1) Terabyte RAID )

(2) SAMSUNG 20X DVD-RW Optical Drives

(1) Thermaltake Toughpower 1200 Watt power supply.

(6) Total RED LED 120mm fans and (3) 40mm Fans + (1) RED NEON


This machine runs Prime 95 - (12) hours stable on all fours cores.
3dmark06 Score - 18,600.


Honestly it sounds to me like you might have gotten either a bad processor or Motherboard, as I have had no problems with mine, also make sure your bios is up to date, and also make sure your ram is compatible with the board. Change some voltages around a bit and see if it helps.

Yea but your not running GX2s, my money is on the PSU. Note that the setup runs fine with a single card.

Sorry - PSU is Tagan 1300 Watt (TG 1300BZ). Today we tried a similar spec Coolermaster unit (sorry I don't remember the model number) and the system behaved the same.

We had the same thought, but I'm now pretty sure the PSU is not the weak link.

Many thanks for the replies.

Jules

http://www.maxishine.com.au/docume [...] d_sli.html


9800 gx2 quad SLI on XFX review

Thanks guys.

I think trying a 32bit OS may be worth a shot. It's either that or we have a dodgy CPU which for some reason Hot CPU etc. is not picking up.

We've changed PSU, RAM and motherboard, removed overclocking (everything's now running at stock speeds) and we're still seeing blue-screens.

Very strange..... maybe roadrunner's right and Intel crippled the new 45nm Quads so that they have a fit in Quad SLI mode ...?

I'll report back if I make any progress. I'm yet to see a QX9770, Quad-SLI rig in any reviews or a spec that anybody has running reliably.

Thanks again

Jules

TRy a different brand of memory.
I have 680i evga mobo, 2 x evga 8800gtx superclocked cards and Intel X6800 extreme cpu.
I went through 3 sets of corsair dominator ram and constant issues. Changed to Geil (2gigs), cost me one third less than the corsair and it works perfectly. I have overclocked the mobo fsb, cpu, gpu's and memory to the max and no probs. regards ed.

yea true, even the link i posted is a QX9650@ 4.0 ghz which I guess doesn't meet that criteria

I run a Q9450 in my 680i at 3.2, and hope to do so in my new evga 790i, so anyone who says "no 45 nm support" is flat wrong.

My money is on Ram or Quad sli, as my 2 8800 GTX's run fine in SLI on my board.

the 790i chipset is flaky when using a quad core.

I have a QX9650, and with some patience and RAM timings / voltage tweaks I was finally able to get it stable at stock settings with 2x9800GTX SLI. I was getting lots of blue screens initially because the BIOS by default did not provide enough voltage to the RAM (1.5V)

These are my settings with the OCZ Platinum 10666 without any hard locks for nearly a week of heavy gaming.

8-7-7-22 2T (stock 7-7-7-20 1T was no good...constant lockups)

TRRD - 15
TRC - 50
TWR - 12
TFAW - 50
TREF - 7.7US

Memory Voltage: 1.8V (1.75V has proven stable as well)
North Bridge: 1.4V
South Bridge: 1.55V

Relax the timings, adjust the voltages, and you should come off stable. I did have 2 bad XFX 790i boards before settling on the Striker II Extreme.

Check out this link, they seem to have gotten them to work with a similar hardware setup as yours.
http://www.guru3d.com/article/quad [...] 9800-gx2-/

Thanks Guys

PraxGTI - That's really helpful. I'll pass those voltages on to the guy who's working on the system. That may be exactly what we need.

Thanks again.

Jules

I would check the exact specification for the voltage and timings for your RAM just to make sure you don't over-volt it

Will do! Thanks again

BAD MOBO.... swap it out with another EVGA 790, and if that doesnt work, RMA the whole board and proc and start over. I doubt very seriously that it is anything else but one of those two items.

Your PSU has more than enough power and is a reliable brand. Im running four hard drives, 2 dvd-rw's and 2 8800 GT's plus 9 different fan motors, and a neon, and a quadcore over clocked to hell, and my 1200 WATT is holding it all fine with room to spare.

You could have gotten a faulty board or proc, it has happened before.
You have already swapped out ram, as you have stated.

The only other possibilty I see is that you are shorting the system on something somewhere. Make sure all your standoffs are correct, and try plugging it directly into a wall outlet, not a surge protector.

Sometimes with these beast rigs, they draw to much power, and the outlet isnt consistent, meaning drops in source power to the PSU, meaning drops in power to the MOBO and Processor. Try a different outlet in a different room just for s-h-i-t-s and giggles.

OH and one other thing... Have you tried plugging any other graphics cards into the board and see if they do the same thing?? what about trying one of the 9800 GX2's on another board?? or trying one on your board and then the other.

Sorry to hit you with so many possibles but I believe I narrowed it down to every possibility and diagnostic you could do. You just got try em and see.