System unstable after SLI

[envy me]

Installed my SLI config, all looked good (DFI NF4 Expert) + 2x256 EVGA 7800GT/CO and I nothiced a few things.

First when in a game loading screen (guildwars for example) I notice the screen jumping around and blinking before loading (Only in the load screen) which hasn't happened before. And I had 1 random reboot which I've never had before also.

Secondly I notice when the computer is sitting normally (not on its side) with the sli config, it sounds like every few seconds, the computer is struggling, very hard to describe the sound, but it wasn't present with 1 video card.

Lastly in my mobo documentation, it mentions that if going SLI, to plug a 4 pin connector from your PSU into the 4 pin connector adjacent the first video card. The ONLY 4 pin connector on my PSU with the compatible size was the floppy disk power connecter (it's not the molex) and I am using that to plug into my floppy. Did anyone who has used SLI have to plug additional power to their motherboard? I am using a Hiper Type-R 580W PSU.


Also, what would be the best way to test my OVERALL stability of the system? I know memtest works for memory, super-pi for cpu but is there a torture test I can run it through that will test out all aspects including video cards?

thanks.

 

[nitromullet]

Lastly in my mobo documentation, it mentions that if going SLI, to plug a 4 pin connector from your PSU into the 4 pin connector adjacent the first video card. The ONLY 4 pin connector on my PSU with the compatible size was the floppy disk power connecter (it's not the molex) and I am using that to plug into my floppy. Did anyone who has used SLI have to plug additional power to their motherboard? I am using a Hiper Type-R 580W PSU.

That is most likely your problem...

 

[sandorski]

You need that power connector plugged in. IIRC you can get an adaptor for that.

 

[envy me]

Originally posted by: sandorski
You need that power connector plugged in. IIRC you can get an adaptor for that.

What is it called and where can I get it?

 

[nitromullet]

Why don't you first test it by unplugging the floppy?

 

[phantom404]

I had to plug in a regular 4 pin power connector to my mobo just like the ones you plug into the back of your Optical drives

 

[Avalon]

I had to plug in a 4pin molex connector and a floppy connector into my drive. The 4pin is above my northbridge in my DFI NF4 Ultra-D, and the floppy is above the PCI-e slots.

 

[envy me]

Well this is just great. I decided to remove and test each card individually (because the problem was not the power connector). Now BOTH cards do the same thing. I get fuzzy screen freezes and I must reboot. WTF is going on with this. I doubt that BOTH cards are bad as the one I had before was working without issues. This was the last peice I needed before completing my pc and I think it screwed everything up. :|

 

[Cuular]

What Power supply are you using? It's sounding a lot like your power supply doesn't have the required power to drive both the graphics cards.

 

[imported_Sincity]

Did you switch your jumpers on the mobo to SLI and enable SLI in the NV Console? Just checking since you did not mention it.

 

[phantom404]

Also bad PCIe slot I wonder?

 

[envy me]

Originally posted by: Cuular
What Power supply are you using? It's sounding a lot like your power supply doesn't have the required power to drive both the graphics cards.

Hiper Type-R 580W ... It should be a sufficient PSU. I only bought it because it is modular and I got it for a decent price.

 

[envy me]

Originally posted by: Sincity
Did you switch your jumpers on the mobo to SLI and enable SLI in the NV Console? Just checking since you did not mention it.

As per my mobo manual, there were no jumpers to be set. I enabled it in bios (finally found out where the setting was) and enabled it in Nvidia console.


Also I switched up monitors. (I plugged into my new Dell 2405) and the screen blinking intermitantly has stopped. I do notice though, while playing my game (guildwars) at 1900x1200 and highest display settings that there is a strange noise every so often, but I am unable to isolate as to where it is coming from. It all looks good for now, I just hope it won't crap out on me.

Lastly, I ran 3dmark 03 to test it, no problems. With 1 card my score was 15782, and with SLI I achieved 25751. I am satisfied with my SLI for now. Thanks for everyones help.