Lowered mem latencies: huge boost!

[msxyz]

I've decided to tweak the bios of my card with Omniextreme edit. I have an XFX 5700U. Since the first day I had it, I noticed how hot it ran. True, it was a good overclocker (could reach 600Mhz on the core and 1050 MHz on the RAM) but when I ran it at stock speeds I was a little disappointed.

Yesterday I took the chance to download the BIOS and examine it with Omniextreme edit. Core voltage was set at 1.4V. A little high, considering that at 2D is only 1.1V and NV40 (which are built by IBM with the same process) use 1.3V. So I tried to lower the core voltage and see if the card was stable enough. I fired up some demos and I noticed that the card temperature was 5-6 degree lower under stress while still being able to hit 520+ MHz of core. Not bad!

Next, the timings... I knew that DDR-2 had higher timings but those set in my BIOS were... very conservative! 21 24 14 7 8 :retard: I spent nearly two hours changing one parameter at time, rebooting and testing efficiency and stability... while I could lower the memory timings down to 16 20 10 5 6 I preferred to keep some margin and go for 18 21 12 6 7 instead (memory is still able to surpass the 1 GHz mark)

The performance boost I was able to obtain surpassed my wildest expectations! Just some figures at stock speed

3DMark2003 (Det 65.73 quality mode, no optimizations): 3720 > 3980
Doom 3 timedemo (1024x768 high quality, no aniso) 25.6 > 28.5 and with shadows disabled from 32.4 > 40.7 !!!

I can say I've beated the sh!t out of this card (xmasgrin)

[rewt]

Congrats :)

I use these timings on my 5900NU 128MB DDR

Timing A: 64
B: 17
C: 19
D: 11
E: 6
F: 6

Memory overclocks to 1020MHz without issues. (BTW all timings except for Timing A were obtained from a stock BFG 5900XT bios) I got a little help with timing A from jimmor here on these forums. ;)

[jimmor]

Congrats :)

I use these timings on my 5900NU 128MB DDR

Timing A: 64
B: 17
C: 19
D: 11
E: 6
F: 6

Memory overclocks to 1020MHz without issues. (BTW all timings except for Timing A were obtained from a stock BFG 5900XT bios) I got a little help with timing A from jimmor here on these forums. ;)


Why did you stick with the timings of the BFG XT bios, rather than finding out what was best for your card/bios/memory ??

For instance, have you tried 9-19-11-5-6 ??

And as you know my 59xx bios modding guide also indicates that the bios timing string structure covers more than just these five values !

[rewt]

Why did you stick with the timings of the BFG XT bios, rather than finding out what was best for your card/bios/memory ??

For instance, have you tried 9-19-11-5-6 ??

And as you know my 59xx bios modding guide also indicates that the bios timing string structure covers more than just these five values !

Because I'm happiest with the BFG XT timings ;) They seem to provide the best configuration to increase performance without decreasing my o/c'ing ability.

I have tried many other configurations, some leading to flashing screen and corrupted images ! I didn't want to risk damaging the card.

Yes and those who have not seen Jimmor's BIOS guide (http://www.nvnews.net/vbulletin/showthread.php?t=29230&highlight=jimmor+bios+guide) should definitely give that a look as well :)

[rewt]

Ahh jimmor you have updated it! I shall have to give this a try ;)

[Kev1]

I followed Jimmor's guide for lowering memory latencies and its been working GREAT for months :) I got a 150 point increase in 3D Mark 03. Not as much as msxyz did but I tried to be conservative.

Am very happy with the outcome :)