7800 GT SLI not recognised

[JakeTheAlbatross]

Got a big problem....

I have 2 PNY 7800 GT's slotted and the forceware drivers refuse to use them in SLI. Both are recognized and show in the device manager as 7800 GT's, but instead of a check box to enable SLI (in the advanced diplay properties), I get "You must remove any graphic cards that are not compatible with NVIDIA Scalable Link Interface (SLI) technology before you can enable SLI."

I spent 2 HOURS on the phone with a very nice PNY support person as I swapped the cards around, installed drivers, and did just about everything we could do. Both cards appear to be working fine, and like I said, both are seen in the device manager, just no SLI. I've updated the MB bios and the cards seem to have the same video bios.

This is driving me insane! I'm about a day away from returning the epox board (taking a 15% restock hit) and picking up a A8N deluxe and seeing if that works for me. I am very happy with the board otherwise, but I need this SLI to work.

If anyone has any ideas, I'm all ears and would appreciate any help.

Thanks,

Jake

Opteron 165
EPOX 9NPA+ SLI (latest bios installed)
2 x 1GB OSZ 3200 platinum
WD Raptor 74 GB
Zalman 9500
2 - PNY 7800 GT's (not yet in SLI mode due to technical difficulties)
600W Ultra X-Finity PSU
Lian Li V1000 Black w\ Window

 

[otispunkmeyer]

i honestly have no idea

i presume you bought the cards together at the same time? (not that it matters anymore since nvidia removed that block)

silly q but does your board have a SLI selector?

you need to change the board from 1x16 to 2x8 ie 8 lanes to each pic-e slot rather than all 16 lanes going to just one

 

[otispunkmeyer]

http://www.ocworkbench.com/2005/epox/9NPA+SLI/g2.htm

right looks like you have a selector card right inbetween the 2 slots.....are you POSITIVE that this is in the right way round? if it is are you SURE its seated proper

 

[Elfear]

Does the Epox board have jumpers or a card you have to switch around for SLI? Make sure the jumpers/card are/is in the right position. The switching device should be right between the two cards. Other than that I have no idea.

 

[fliguy84]

yeah, make sure the SLI paddle switch is on "SLI Mode" (Like this pic), connect the SLI connector on both cards (make sure it fits firmly) and get the latest 81.98 drivers from nvidia

 

[BatmanNate]

Do you have the latest drivers? If they are different versions of card then they weren't supported in SLI until recently, right?

 

[Woofmeister]

Let's start with the obvious. SLI jumper in SLI Mode? SLI Bridge connected to both cards? Both cards' PCI Express connectors connected to PSU? SLI enabled in BIOS?

 

[JakeTheAlbatross]

First off, you guys were right, the jumper was in the wrong position. BUT before you think I'm a total moron, I'll explain what happened (also in case anyone else has this problem and they are doing a search).

I set everything up outside the case after I got all the parts delivered. But I DID NOT INSTALL BOTH CARDS AT THAT TIME, just one with the jumper at 16+1. Installed windows, drivers , and all that. No problem. Everything works great.

Then, I installed everything in the case, including both 7800's. turned the jumper to SLI mode and installed the bridge. But could not get SLI working.

So... I called tech support and we went though all this stuff and he tells me that the jumper card is improperly labled (he says they've done it before?), so I turned it the other way (to 16+1) and windows still recognizes both cards as 7800's so we continue on and of course nothing works.

Finally after 2 hours, I got to go, I have other plans that evening and he says try reinstalling windows, so I do that too, but that doesn't help. All the while with the jumper the wrong way.

After asking here on the forum, I thought, hey what the hell, they're probably right (everyone knows anantech forum readers are the smartest people on the planet, right?). So I turned it around, put my other 7800 back in and started up and windows says new hardware found. I check device manager and it says it needs drivers for the just installed second 7800 (strange) so i re-installed the SAME forceware driver I already have installed, right over the old drivers, restarted and presto, SLI is now ready. Checked the box in advanced properties and I'm good.

The moral of the story is...

After I put everything in the case, I should have just installed the video drivers again over the old and I could have saved myself some grief.

Hope this helps someone else if they're having the same problem.

Thanks to everyone here for the help,

Jake

 

[Woofmeister]

Glad to hear we could help you out. Enjoy those GT's.