Geforce Overclocking

[nheather]

I've just bought a used Geforce 6800GT which is given me problems - I suspect it's a dud but I haven't totally given up hope.

I think it was previously overclocked, the seller says not but I notice that it's fitted with an after market Arctic Cooler Accelero X1 and the cynic in me says why do that if not for overclocking.

I'm not very familiar with Geforce overclocking so have a couple of questions.

1) Is it possible to tell what the current settings are?

2) If the card has been overclocked, does it remain with the card. That is if the card is removed and installed in a new computer will it still be overclocked. Basically, I'm not sure whether overclocked settings reside on the card or with a PC based overclocking application.

3) If the card is overclocked is it possible to turn it back to stock?

Cheers

Nigel

 

[thegoonden]

Clock settings on that card are not permenant, they are applied at boot (or later) by whatever overclocking software you're using.
You can't really tell if it's been OC'd I don't think.

Can clock the knackers of that one too most likely.


What's it doing to make you think it's been abused?

 

[nheather]

I bought it to breathe a little extra into my son's and daughter's PCs. My sone does more gaming so the idea was to replace his Radeon 9700 Pro with the 6800GT and my daughter would get the 9700 Pro.

When I installed the 6800GT on my son's PC I noticed a small number of flickering lines (one pixel wide) on the windows desktop running at 1280x1024@60. When I turned up to 1280x1024@75 I got loads of flickering lines.

I tried all all sorts of suggestions - totally erasing all signs of the previous ATI drivers, running a much older nvidia driver but to no avail. I was on the point of sending it back when the seller (who claimed it worked fine on his machine) asked if I had another computer I could try it on.

So I tried it on my daughters and it appeared to run very stable. No flickering lines at all on windows even at 1280x1024x75. So I assumed there must be something about my son's PC that it didn't like and informed the seller.

That was about a week ago. Yesterday I was looking at my daughter;s PC and I noticed it still had 3DMark03 from ages ago so I decided to give it a spin. This is a pretty old benchmark and my previous cards (including the rubbish 6200 that had been removed from my daughter's PC) have had no problem with it.

But this 6800GT so problems on virtually every test. These varied from blue smears coming down from top left, to missing textures and odd triangular shapes breaking up the picture. The harder test (Troll Cave) was barely discernable it was breaking up so much.

The problems aren't random - they appear to take the same form each time I run the test.

I suppose I could go back to the seller but I feel that I've accepted the card now.

In both cases PSU is on the limit (350W) but I'm not convinced that is the problem. My son has my hand me down Enermax and previously that had been running a Radeon X1800 GT without any problems.

Cheers,

Nigel

 

[4T5]

You may find the ambient temps in your daughters case are better giving the card cooler air to breathe/cool with.
Sounds to me like a re-seat is worth a try but i read your other thread & don't know whether you have to use the pads to line/level the cooler to make it sit properly.
If you don't need the height then I'd re-seat it all using Arctic silver. Once done I'd search about for old threads on the card & what drivers to use then try 2 - 3 different drivers.
Have you any way of monitoring temps under load with that card, Any sensors on it ?
There will be a point when you can get the card to run without artifacts even if it's on its last legs. The balance will be between temps & clocks.
If the card is still good then improving case cooling/airflow & re seating the cooler with decent thermal paste you should be able to achieve reasonable temps whilst overclocked.
If almost dead you'll just have to underclock it to get cooler temps to stop it artifacting. All is not lost & it'll do the lad until you get a replacement.

Hopefully a re seat & AS & sorting the case cooling out will allow you to run it clocked. Clocked that card will still run loads of decent titles & even at default it will run HL2/CSS/FarCry/BF2 etc etc etc etc

 

[nheather]

I'm back thinking that it's a driver problem.

I've noticed that when I run 3DMark03, in the first test (WWII Air Battle) the FPS, Time and Frame numbers are missing from their fields at the bottom. Then when I look closely at the blue smearing that comes down from the top left I see that it is the numbers but smeared out big.

I've tried underclocking to minimum 175MHz GPU and 500MHz for memory and I get exactly the same.

I'm now back on driver 77.62 and the result is exactly the same.

I don't think the card is overheating and its hard to imagine memory failure producing such repeatable results - especially at different screen resolutions.

Puzzled now.

Cheers,

Nigel

 

[nheather]

I think I might have fixed it, the 3DMark03 appears to run okay now anyway.

I made the following BIOS changes

AGP Apeture - changed from 128MB to 256MB (I'm not entirely sure what this does. I didn't think it had to be as bi as the RAM on the graphics card but I set it to equal anyway)

AGP Speed - changed from AUTO to 8x (in theory this shouldn't have made a difference because AUTO should have set itself to 8x)

But after I made these changes the 3dMark03 changed from being quite corrupted to running fine.

Fingers crossed, it wasn't a one off.

Cheers,

Nigel