BFG 8800GTX OC Help

[Sabre2]

I am tired of using nTune to set the core clock and memory clocks manually every time I restart my computer so I looked into flashing the BIOS on my GTX card.

It's cooled with a Stealth Rev.2 and I know it can handle 694 core and 986 memory since I run it like that all the time. But the problem I ran into is during this whole thing, i get the option for Shader frequency and I have no idea what shader frequency to expect. Right now it says 1404 (stock) in NiBiTor and i don't know if I should mess with that at all. I also read that it is linear to the core speeds

Does anyone have recommendations or maybe places for me to go (links) and learn more about fine tuning my card for more performance? I searched for 3 hours last night trying to figure out what to do and I just can't find information on all of this. I managed to break nTune now and I can't find the sliders to increase the core/mem speeds and I just want to avoid all this by flashing the bios on my card.

I'm using Vista x64 too if thats a problem. I was able to get my bios with nvflash even though it gave me a unsigned driver error afterwards it still dumped my bios to a file (yes I disabled the forced driver signing with F8 at bootup).

Thanks

[wreckage]

Dude, download Rivatuner

I can run 690/1530/2140 on stock cooler, with windows open ofc.

Edit: In your signature it sais: (700Mhz/2200Mhz), what do you mean by that? Have you changed Bios to Ultra?

[Sabre2]

I put that there cause at one point I thought I could run it that fast. Turns out I feel more comfortable running my core at 694 and my memory at 986 on the memory making it 1972mhz (think you have to double it)

Also I figured out, it doesn't do it as precise in nTune, when you put 700mhz its actually 712mhz, seems to jump in steps.

I read somewhere that Shader clock scales as core clocks go up, but what is the correct formula?

Rivatuner, I'll have to look into that. Thanks.

I was reading here by the way... apparently being able to control shader will allow for a larger core clock from what I understand. If I could make my core clock a nice smooth 700mhz it would make me happy, I like round numbers :)

http://www.overclock.net/nvidia/145645-nvidia-release-shader-overclocking.html

[gOtVoltage]

I put that there cause at one point I thought I could run it that fast. Turns out I feel more comfortable running my core at 694 and my memory at 986 on the memory making it 1972mhz (think you have to double it)

Also I figured out, it doesn't do it as precise in nTune, when you put 700mhz its actually 712mhz, seems to jump in steps.

I read somewhere that Shader clock scales as core clocks go up, but what is the correct formula?

Rivatuner, I'll have to look into that. Thanks.

I was reading here by the way... apparently being able to control shader will allow for a larger core clock from what I understand. If I could make my core clock a nice smooth 700mhz it would make me happy, I like round numbers :)

http://www.overclock.net/nvidia/145645-nvidia-release-shader-overclocking.html


the Core raises in steps.....685,,704,,729,,756,,and so on......

Raise the memory First .....Then the Shader .....and finally the GPU..

If you do the GPU first it will affect the memory Overclock with the exess heat from GPU....

The GPU,, sits in the middle of memory...so when the GPU is Oced it lets all its heat into the memory banks on the card...

The higher the Memory and Shader the better the Performance,,compared to having a High GPU and low memory...

example: 700mhz//1764mhz//2200mhz is better than 729//1632//2000mhz

The memory will gain bandwidth and shader performance....The faster the shader and memory can run the more pixels you can process at one time...The GPU will not gain much performance going from 700-729 when compared to the Memory and Shader...

Use RivaTuner 2.06 and set the Fan too 100% all the time in all modes...this will help you alot...!this will allow a more stable overClock...mostlikely some more MHZ too..Just take your time and.....while the GPU is @ 700mhz and try shader 1674//1729mhz and memory @2200mhz.. Its a GTX and im being conservative:D ...

[Sabre2]

I ran into a big problem last night, I know for a fact that my GPU does not like being above 700. At 700 I got 30 some artifacts in one frame then a blue screen of death.

Stupid me tried lowering memory and shader and to see if going to 715 core would pass some magical barrier (yay puff the dragon), when I flashed the bios and tried to restart windows, it would crash in windows.

Thankfully I could start in Safe Mode and get my bios files if needed, but the only problem is I have no floppy drive or bootable usb thumb drive to flash anything with. Tried making a bootable flash drive but x64 needs driver signing so I couldn't install a virtual floppy drive to make a bootable flash drive either.

I made a bootable CD, and put my bios files on there with the flash utility but since I have a SATA dvd-rw drive, the CD-Rom drivers on the boot floppy couldn't find the cd-rom drive. Eh.... so finally I hooked up an old hard drive, dumped it all there, rebooted with the cd to find out that the nvflash version I had was for windows and I had to download one for dos.

Took me all in all about 3 hours to do and I learnt my lesson, I can't go above 700 core with my GPU. Reading what you said though, I thought core made much more performance, I was wrong then.

Thanks for the advice, I'm going to lower the core a bit and start OCing the memory and shader. I just don't know what numbers to start with or try out. Any downside OC'ing the memory? Should I clock in steps of 20mhz (going from 900 to 920 for a total of 1840) and do the same on the shader? If ATI Tools artifact test runs for 10 minutes I can keep going higher till it starts freaking out?

[Sabre2]

By the way, what kind of problems did you all run into? Can you flash the GTX if you use a PCI card to boot with in dos? What is the worst I can expect if I OC the memory too high? the shader too high?

[Timbosan]

dont flash it with clocks you dont know are stable! try them first as suggested by using rivauner. only when you are 100% sure flash the card. you can flash the gtx while using a pci card to run screen but not sure on the nvflash procedure.
shader 1 step too high should show small white squares especially in mist and smoke scenes, 2 steps too high it may full lock. mem too high usually gives wierd translucent triangle shaped things or streaking of colours.

[Sabre2]

I'm using ATI Tool to find artifacts and Rivatuner. I find that I can run stable at 690 core, 1950 memory, 1500 shader for atleast 6 hours of atitool artifact scan. But when I have my memory at 2120 and my shader at 1640 I'm still seeing artifacts at 670 core.

What do you use to see if there is display corruption Timbosan? in Ati tool all I see is yellow specs when the stuff isn't working right. Heck when I was running 695/2120/1640 things would run fine for a minute then the whole freaking block would light up yellow for one frame. Now this doesn't happen at 670 core but im still seeing little artifacts around the edges so I lowered to 665 and going to run it while i'm in the shower.

Problem is, ATI Tool hasn't been detecting the artifacts, I've been seeing them with my eyes instead so... if I hop in the shower, I'll miss them all and chances are ATI Tool will not have seen them for me.

[Sabre2]

Whats better:

660MHz core, 2120MHz Memory, 1640MHz Shader

or

690MHz core, 1950MHz Memory, 1500MHz Shader

?

Those are my two options so far, seems like the first one is fine tuned and passed ATI Tool for an hour.

Going to try 3DMark06 and see which one yields better results I suppose.

[Sabre2]

Just ran 3Dmark06

First profile 660/2120/1640 13861 3DMarks
Second profile 690/1950/1500 13862 3DMarks

Is that possible? I will do them again tonight.

[Timbosan]

i use 3d mark 03 nature to test max current draw, which shows you if your core is too high (it will hard lock if it is too high).
i use 3dmark 05 & 06 GT2 (firefly forest) to test memory artifacts, and i use 3dmark05 GT3 (canyon flight) and 3dmark06 GT4 (deep freeze) to test shader artifacts.
the memory artifacts show up as green streaky flashes in firefly forest. shader artifacts for me are small white squares or flashes of tiny white or coloured squares or circles (like a dim fireworks flash).

first, try setting 1107 on the memory at stock gpu & shader clocks. if it runs 3dmark06 GT2 (firefly forest) test repeated ~8 times without artifacts it should be stable. if not, drop memory frequency until it will run 8 repeats (not loops!) of 3d06 GT2 without artifacts.

then move to your gpu - try it at 684 (i think its ok at his speed form what you said as it will hard lock when gpu too high), with shader at default clock, memory at 1000 (if it passed the test) otherwise at the max stable mem freq.
if that is stable, bump up the gpu to 702 and repeat test. if that is stable, increase shader to 1674, and repeat 3d06 GT2 x 8 repeat test. if stable, bump shader to 1728 & repeat tests.

So:
1. set default clocks for gpu & shader
2. increase mem freq to 1107 MHz
3. bench 3d06 gt2 repeated 8 times - if it passes increase it to next step up (1152?) and repeat test - if it passes move to next step etc otherwise decrease mem freq till it can pass above test with no artifacts.
4. increase gpu to 684 (leaving mem at max stable freq) and repeat the test - if it passes increase it to 702 & repeat test - if its stable move to next step otherwise lower gpu till it passes.
5. increase shader to 1620 (leaving gpu & mem at max stable freq) - repeat above test - if it passes move to next step if not lower it & repeat till its stable
6. increase shader to 1674 - repeat above test - if it passes move to next step if not lower it & repeat till its stable
7. increase shader to 1728 - if it passes move to next step if not lower it to 1674 & ensure its stable

After that you should now be at your max clocks. id guess you will end up somwhere near 684/1674/1053 (gpu/shader/mem)

[Sabre2]

Thank you so much, I noticed the artifacts in firefly forest with 660/1060/1640 so I knew there was something wrong. Was showing up as flashes up in the trees.

I'm going to reflash my GTX to something much more comfortable now and test all this with RivaTuner.

I'm very close to breaking 14k 3DMark06 so that will be my goal soon... for normal operation that is. After I find the values for my GTX I am going to OC my CPU a bit more and I should break that 14k soon enough.

[Sabre2]

I can't go without artifacts above 1000 memory, how lame. Whats causing this? Just got unlucky with the card I have?

[Sabre2]

With a days testing, my initial 690 / 975 / 1500 proves to be trustworthy. I thought I'd get more out of this card though, but thats what i will settle with. I can run 690 / 1000 / 1620 but that seems to be the absolute max and I don't want to push it that hard all the time.

I'm going to flash my GTX BIOS with 675 975 1500 to be on the safe side and that will be my mode of operation from now on since i'm more comfortable with those numbers. Scored 13850 3D Marks with it.

[dengyong]

I still use ntune. I've tried riva and adjusted core and shader clocks separately but it doesn't help my card.
I also get no improvement in 3dmark06 running the memory past 1100 on my gtx. there's a link to my score in my sig.

[Tipsi]

Hello every1. I'm new to this forum and in fact new to modern OC'ing also. Got a new setup few months ago and started learning the secrets of overclocking.

My EVGA 8800 GTX ACS3 seems to be a little disappointment since I've only managed to get 621 / 1485 / 1008 out of it. At 648 3DMark06 and AtiTool both do a total stop for the whole system and the next step with memory begins to produce artifacts in AtiTool test. I've kept the shader freq. linked during most of the testing sessions. Fan is locked to 100% but it actually makes no difference to my results, crashes at the same clocks. Temps are at tolerable levels about 65-70 loaded. Any suggestions how I could improve my GTX's performance even further. I will try unlinking the shader but I've kinda lost my faith in this card. Got 12920 p. in 3DMark06 just today when I realised I should turn Vertical Sync off to get more than 60FPS :D 13000 is so close.....

Have anyone found a way to increase GPU frequency in smaller steps than 27?

My setup:
Asus P5K Deluxe WifiAP
E6600 @ 3.6
Cellshock PC8000 @ 600 5-5-5-15 (haven't touched subtimings yet)2.25V
and the sorry EVGA 8800 GTX ACS3
Thermaltake Toughpower 750W
WinXP

[dengyong]

Hello every1. I'm new to this forum and in fact new to modern OC'ing also. Got a new setup few months ago and started learning the secrets of overclocking.

My EVGA 8800 GTX ACS3 seems to be a little disappointment since I've only managed to get 621 / 1485 / 1008 out of it. At 648 3DMark06 and AtiTool both do a total stop for the whole system and the next step with memory begins to produce artifacts in AtiTool test. I've kept the shader freq. linked during most of the testing sessions. Fan is locked to 100% but it actually makes no difference to my results, crashes at the same clocks. Temps are at tolerable levels about 65-70 loaded. Any suggestions how I could improve my GTX's performance even further. I will try unlinking the shader but I've kinda lost my faith in this card. Got 12920 p. in 3DMark06 just today when I realised I should turn Vertical Sync off to get more than 60FPS :D 13000 is so close.....

Have anyone found a way to increase GPU frequency in smaller steps than 27?

My setup:
Asus P5K Deluxe WifiAP
E6600 @ 3.6
Cellshock PC8000 @ 600 5-5-5-15 (haven't touched subtimings yet)2.25V
and the sorry EVGA 8800 GTX ACS3
Thermaltake Toughpower 750W
WinXP

You have both power connectors pluged in, correct ?

[Tipsi]

Yes. There are total of 3 PCI-E outs on my PSU. 2 6-pin and one 8-pin. I'm using one 6-pin cable and the 8-pin cable with adapter (came with the PSU) -> 6-pin. This is because the 6-pin cables are removable but the 8-pin cable is not so I have one less rope messing the interior of my case.

Now I've tried every combination with the power cables and unlinking the shader from core speed and the results maintain. 648 GPU is just too much for this card I guess... :(

*edit: Unless.... EVGA has a KO version of the same ACS3 cooled card w 626 core, 1000 memory and 1450 shader speed. It doesn't fit into the steps I'm getting 621 -> 648. Have you tried to take the BIOS from one of the pre.overclocked KO cards and put in a standard GTX? Just to see if it'll have different clocksteps.

[Sabre2]

I'm at 650 core 950 memory and 1450 shader and Crysis is getting all sorts of weird stuff when I use a flashlight on my guns. I'm starting to think I should have never messed with it.

I can't run the game maxed out at Very High settings, it lags too much in certain areas... but a friend of mine has an 8800GT and he says everything at Very High and nothing lags like what im describing.

Oh well =(

[Tipsi]

You should check if Rivatuners monitoring screen shows your clocks the same as you adjust them. For me it doesn't show the same figures, the actual core speed goes up in 27MHz steps and not 1 @ a time. Same with Everset. Shader has a step of 54MHz if recall correctly. For memory its 18MHz. Correct me if I'm wrong because I'd like to increase speeds slowly 1 MHz at a time. If you flash BIOS does the speeds match with what you put to Nibitor?

*edit: oh. I really have to change the color of my sig. It's horrible! :eek:

[Timbosan]

SABRE2 - dont stress its all supposed to be fun yeah? Games can sometimes show up artifacts better than benchmarks. Use rivatuner to overclock - ntune etc suck ass im not kidding riva is the best no questions.
Unlink the shader if you havent already - go into power user tab, go into overclocking/nvidia tab & put a '1' in the box corresponding to 'vista specific features'. Exit riva then restart it & you should now have a separate slider for the shader.

Try this:
Core = 684
Shader = 1512
Mem = 900

Does that artifact or lock up?

if it artifacts try:
core = 684
shader = 1458
mem = 900

if it locks up try:
core = 675
shader = 1512
mem = 900

let me know what happens

[Sabre2]

Thanks Timbosan, I will try tonight. The weird stuff in Crysis last night did not go away when I flashed to original bios of 600/900/1404 so its a problem with the game unless it's possible to damage my card and this will always happen.

If I get time, I will do everything proper tonight and post results. I have a feeling though that my card is not a very strong overclocker. I can guarantee anything above 684 core will not work though. If raising clock speeds go in steps, why can I run at 699 (artifacts galore) but then have a hard lock at 700 almost immediately running ATI Tool? Shouldn't the next step be 704?

Anyways, more testing to come. Thanks for all the help so far.

[Tipsi]

Hi all. I was wrong about the core clock increasing in 27MHz steps. There are also 9 and 18 MHz steps. Here's what I found out going up up from factory default:

576 -> 594 -> 612 -> 621 -> 648 -> 675 -> 684 -> 702 -> 720 -> 729

Couldn't go further, system locks up. Did this with Rivatuner.

If you adjust core slider and shader is linked to it, shader speed may increase even if actual core speed doesn't.

Testing continues here also. Currently @ 621 / 1512 / 1008 stable no artifacts. 3DMark06 13149 ! :banana: