Does using the lower PCIe slot lower your graphics performance?

[jermaink]

I've just run 3DMark05 on my computer (see setup below), though at stock settings I was only able to crank out 3850 3DMarks. I overclocked the X800XL to 475/575 (about 18%) and only ended up getting about 4400 3DMarks. This is lower than average performance for an X800XL (stock usually gets about 4800 3DMarks). Could this be because I'm using the lower slot on my DFI Nforce 4 Ultra-D?

 

Also, the top PCIe slot is blocked because of my Thermalright XP120 (though I didn't install it in the optimum way for space near my PCIe slot). Anyone been able to use the top slot of their Ultra-D with an Thermalright XP120 and an Arctic Cooling Silencer?

[red930]

It should fit fine, it fit an x850xt pe in the computer sitting next to me. Just orient it so the heatpipes are on the bottom, with the overhand over the memory slots.

[loc.o]

Used me card in top slot without probs with the XP120 and silencer. Pipes towards bottem case.

 

Did you set the jumpers in SLI mode before you started using lowest slot for GFX so it runs x8 instead of the default x2?

 

[jermaink]

Nah, I didn't touch the SLI jumpers. Being a Ultra-D, I assumed that they would be set for 'non SLI' mode. Also, I mounted the XP120 the other way, so I'm probably going to have to clean/reapply AS5 before I can switch it all back.

 

But would the loss in preformance be due to the loss of bandwidth, or could it be something else? Even the AGP version had better performance (acutally it was better than the PCIe version).

[loc.o]

AGP =x8, lowest PCI-e slot at default =x2, thats makes the diff i guess. The difference between x16 (top slot) and x8 (lowest slot SLI mode) is neglactable.

[jermaink]

It does make a difference. I just checked. I just switched the PCIe slots, for an extreemly tight fit, just to run 3DMark05, and it made a big difference. Though I can't mount the fan properly on my XP120, and won't be able to until I reorientate the XP120. At stock speeds (just above, 400:500) I got 5072 3D Marks (v 3858) and OC'ed to 475:575 I got 5869 (v 4391). Not bad for an X800XL, and temps never got higher than 48C, though the 3DMark05 session didn't really last long.

 

Thing is, now I'm going to have to change my plan about getting a Zalman NB47J northbridge heatsink. Anyone know of a replacement northbridge heatsink which won't wail whenever I startup/reboot the computer?

 

Also, does anyone know WHY this happens? And if it is possible to get my other PCIe slot to give the same performance?

[Boppo]

As said, try moving the SLI jumpers. That makes the lower slot 8x instead of 2x.

 

For the NB cooling, there are a lot of threads about that subject. Do a search. There are at least 7 threads in the modifications forum on it, including some pics of things people have done.

[jermaink]

Yeah. I remember one about some Arctic Cooling NB cooler being decent. If you've had experience with it, is it low enough, and does it wail when it starts up?

 

I'll try moving the SLI jumpers to see if that makes the difference. Thanks for the info.

[thefabe]

Use the evercool Vc-Re. it is the recommended chipset fan it"s the same hight as the stock so if your card works now it will still work after http://www.dfi-street.com/forum/showthread.php?t=52950

[woz_mann]

http://en.wikipedia.org/wiki/Accelerated_Graphics_Port ........ AGP 8x

A 32-bit channel operating at 66 MHz, strobing eight times per clock, delivering an effective 533 MHz resulting in a maximum data rate of 2133 MB/s (2 GB/s); 0.8 V signaling.

 

http://en.wikipedia.org/wiki/PCI_Express ...... a 16 lane (x16) PCIe card would then be theoretically capable of 250 * 16 = 4 GB/s in the direction

[loggan26]

Its been covered before in here, running in the bottom slot at x2 you do notice a drop in benches, set your jumpers to sli and x8 and your set back to normal benches.

 

And as mentioned the evercool for chipset.

 

Logan

[Clarity]

Wow....this is some very useful information. I'm going to move my card back to the top slot, I remember how moving it didn't affect the temps of the MB. Recently there was an unexplained drop in performance in my games. Now I know why... Thanks to whoever bumped this thread, this helped me a GREAT deal.