Graphics Problem !

[technojunky]

I recently had a few problems with my PC that I thought were related to the XFX 7900GS 256MB Extreme graphics card. I therefore bought a second-hand BFG 7900GT 256MB on Ebay to see if it would solve the problem.

I installed the 7900GT (which is supposed to be a superior card to my 7900GS) and ran 3Dmark06. The 7900GT scored 4847 on the standard 3dmark06 settings compared to 5435 scored by the 7900gs. I have run the test on both cards twice with similar results.

Could this mean that the BFG 7900GT 256MB is faulty ?

Any helpful advice would be much appreciated.

Thankyou.

 

[killersheep34]

If the 7900GS is an extreme edition, I would assume that the clocks are at a higher rate then normal? Perhaps the faster clocks is giving it the extra gain in 3dmark.

 

[postmanfw]

Use gpu-z to see what clocks each is runing at. The gt is a better card if both were stock versions but as the gs is extreme it is probably clocked higher than the gt.

What problems were you having with the gs?

 

[SBD]

well the 7900Gt is like a 7800GTX and the 7900GS is like a 7800GT. (GT has 24 pipes GS 20 pipes) I'v had a 7800GT and a 7900GT. The 7900GT should be a fair bit quicker and shouldn't do worse in 3D mark. have you got the latest drivers?

 

[technojunky]

Thankyou for the posts.

Yes, the XFX 7900GS is the Extreme version. Both cards have 256MB of memory.

I ran GPU-Z on both cards and the difference in results were quite astonishing :

7900GS 7900GT

Memory Size 256MB 256MB
Memory B/W 51.2GB/s 43.5GB/s
GPU Clock 600MHz 475MHz
Memory 800MHz 680MHz

Despite the fact that the 7900GT has 24 pipes and the 7900GS only 20, am I right in assuming that the higher clock speeds of the 7900GS Extreme is the reason for the better score in 3DMark06 ?

I found that the 7900GS was getting very hot in my system and causing it to preiodically to shut down. I therefore bought the 7900GT to verify that it was definitely a problem with the video card and not something else in the system.

Thanks again for the posts.

 

[fraps]

I think it is the clock speeds - those clocks are a big increase over a standard 7900GS

Get ati tool .26 and underclock your 7900GS to the 7900GT clocks and run 3d mark again OR

overclock your 7900Gt a bit and see the increase and guess what it would be if overclocked the same as the 7900Gs or

just google to obtain scores on various tests done on these cards to get an idea

note that standard clocks for the 7900GS and 7900Gt are 450/ 660

 

[technojunky]

Thankyou for the reply fraps.

I couldn't believe the results when I compared them, perhaps that is why the 7900GS gets so hot !

I run the ATI tool and post the results.

Thanks again.

 

[Blackhawk47]

that does seem interesting and yes your right it will run a lot hotter. maybe even artifact. my 7800gt isnt clocked that high though i think i will have to run 3dmark 06 and gpuz soon to.