Help - poor performance with X2 & GFX7800

[philg]

Ok this is a last resort request for help :confused:

 

I built my X2 4400+ system 2 weeks ago (full spec in sig) and since then, I have been dissapointed with the performance in games.

 

I think there may be a problem with my 7800GFX because 3DMark gives only 3500-4000 points, and CS:S gives 70FPS at 1600x1200.

 

Whilst thats not bad - its hardly good...

And then, last Monday, for some unknown reason, it decided to wake up and play propperly. 3DMark shot up to 7300 points and CS:S up to 160FPS (same settings)

 

For about 4 hours - then back to "normal" slow

 

Since then, Ive tried the following since Monday to get back to the proper performance but nothing seems to work:

• Changed PSU
  
• Removed 2x512 RAM sticks
  
• Swapped PCIe slots
  
• Tried XP 32 and x64, in dual and single cpu mode
  
• Tried various revisions of forceware (77.72, 77.76, 77.77, 80.40)
  

 

Also, Ive tired OC' the CPU and RAM - made no difference. (On monday it was fast both at 212FSB and stock speeds - Before monday and since, its slow on both)

 

The CPU temp is between 39 - 45

The GFX temp is between 45 - 60 (depending on load)

The NF4 Chipset temp is between 49-52

 

I have yet to try downgrading the NFocre shipset drivers from 6.66 to 6.39 but I doubt that will help..

 

What have I missed ???

 

Thanks,

[philg]

One thing I've just thought of, I havnt connected the "floppy" power to the main board - (all the others are connected) because I dont have 2 floppy power leads.

Why DFI couldn't put 2 molex's instead of a 1xfloppy and 1xmolex power god only knows (I have loads of them!)

 

Do you think this could be the problem - the first thing I'll try is ripping out the FDD and using its power to the MB...

[tristancarton]

i frist thought it sounded like a chipset driver problem but you said it started to work fine on monday which would indicate the chipset driver was probably okay. (though i think it would be best to check in the nvidia control panel to make sure it is running in pci-e 8x or pci-e 16x speed) however now i think it sounds like a throttling problem due to a power issue. from what i understand 6800 and 7800 cards run low clocks in 2d and then throttle up to higher speeds upon 3d apps. my best guess would be that your card isn't getting enough juice and is therefore hampered due to lack of an ability to throttle up to normal speeds.

 

also want to make sure your a64 isn't perhaps throttling down to a heat issue. this was sort of the case with a guy with a similar situation over at nvnews.(though he had a p4)

 

http://www.nvnews.net/vbulletin/showthread.php?t=54140

[Boppo]

A couple of questions:

 

1. Are you overclocking the GPU?

 

2. Did you plug in the power connector into the 7800? You should have gotten a warning message when entering Windows if you did not do this.

 

3. Have you searched the forum? Seems I have seen other posts about dual cores and 7800s not behaving themselves.

 

NVidia does indeed throttle down the GPU on this card for 2D, if there is not enough power for it, or if decides it can not run stable at the Core and Mem speeds it is told to run at.

[rise4310]

i think its a dual core issue. i've seen some stuff at extreme among others about this. i wish i knew more to help but i would focus on the x2 and how the cores are being utilized. i know you said you ran it in single core and dual core but i just have a hunch some digging there will bail you out.

[philg]

Thanks for the input guys, much appreciated.

 

In answer to the questions:

 

1) Im not overclocking the GPU (I havnt figured out how yet)

2) The GFX's PCIe power cable IS connected

3) I have searched but didnt uncover too much - I will try some more.

 

I've now connected the floppy power cable to the m/b - it didnt make any difference....

 

I will try powering the GFX from a second PSU just to make sure its not a juice issue (I have tried 2 PSU's already - 550w and 580w)

 

Also, the installs are both pretty fresh as I only set it up 2 weeks ago, and the problem happened since the first boot (only Monday it was ok - wierd).

 

Im pretty sure the main CPU isnt throttled... I have not got CnQ enabled and its running at 38-42 deg... hardly hot! Also, boot and windows performance is pretty swift.

 

If its a dual core issue, why would it have worked on Monday :S - I will investigate this further - maybe downgrade the bios to pre-dual core support - anyone know where I might find an older bios for the SLI-DR?

 

Where do I find the PCIe speed in the control panel - on the general page, it says "Bus: PCI express x16" is that it? In which case, no problem there....

 

Thanks,

[philg]

Ahaa I think I found the solution thanks to you guys.

 

After reading a thread on the NVNews board, it would seem that maybe Dual digital out is the problem.

 

To test this, I disconnected my second LCD panel and rebooted.

 

CS:S FPS back to 150 (3dmark crashed in x64 but looked good before that)

 

Then, I rebooted again, this time with the second LCD on the DV-Analogue adapter - and thats fine...

 

It seems that 2 panels each on digital is not well liked by the GFX with these drivers (I hope they fix it - but for now I;ll leave the second panel on the analogue input!)

 

Thanks again,

[rise4310]

sweet, good info, thanks for posting back!