nvlddmkm.sys bsod after GPU flash?

Hey guys, i'm running a 9500m GS with the dox 185.85 drivers.

i flash my gpu to 625 / 475 fine for a few days, but now, when i flash, i restart and get a bsod with the error nvlddmkm.sys crash dump. then restarts and does the same thing, until flash back the oldbios.rom.... it was working for a few days, now it don't, any ideas?

i'm running Win7, and after a fresh format it still does it?

any help would be appreciated.

 

Anyone??????

 

a shot in the dark , see last post eventually

http://www.vistaforums.com/Forum/Topic5276-21-1.aspx

 

Sounds like you've got an unstable overclock there.

 

From my experiences it has to do with the 9500/8600 core and Vista. Once I downgraded to XP, regardless of my overclock/temps I never saw that error again.

Before I'd see it once every 30 minutes of gaming.

 

If you've flashed your GPU's Extra clocks, it may be that before, you weren't accessing that level after startup.

Now for some reason, you're starting off at the Extra level and due to instability from too much overclocking, you're getting an instant BSOD.

Either way, go lower your clocks.

Also what are your core, memory, and shader clocks? Its best to keep core:shaders linked in a 1:2.5 ratio and not bump up memory too high.

 

Anyway, you're quite lucky that your GPU still survive and give BSOD only.

@TevashSzat: It is good to keep core:shaders linked in a 1:2.5 ratio? Because I am having 600:1385, should I change it to 600:1500?? Because I saw a lot of users adjust about 1:2.25 ratio.

 

Who? 10char

 

Right infront of you, me and tehsuigi. Not really exactly 1:2.25(just below 1.2.5). There are more. You can go Acer forum there and have a look on all AS 6920G threads. You can find a lot of it. I don't have time to dig out the person name. The GPU I talking about is Geforce 9500M GS.

 

Different generations of GPUs use different ratios for core/shaders.
The 8 Series (and its cousins the 9300M G, 9500M GS, and 9650M GS) use a 2-to-1 shader-to-core ratio by default, while the 9 Series and on use a 2.5-to-1 ratio.
I don't believe there's any performance loss to be had by having the shaders on a different ratio (mine is 2.28-to-1).

 

Actually, was does the Shader Clock do?
If the performance is not related to the shader clock, then, what for to overclock it?

 

The core clock is the speed that the GPU operates. The shader clock is the operating speed of the link between shader processors such as vertex, geometry, and pixel shader. The shaders are linked to the core clock in a tight ratio, in this case with the 9-series, 1:2.5. Lastly, memory clock is the speed of memory chips. The key to overclocking is to have a good balance between the core, shader, and memory so nothing will be bottlenecked internally within the GPU. Most games and benchmarks benefit the most from shader speed so if you plan to break out of core/shader ratio, it is best to push the shaders first, then the core, then the memory. However, you should still keep a modestly tight balance between the core/shader, core/memory, and all three clocks overall, otherwise you may not see any performance, and even a loss in performance, if only one clock speed is pushed alone.

 

Ok, well i've just tried 500 / 420 (original is 475 / 400) and i dont get the bsod, but started cod4, artifacts all over the place.... this is wierd, i oc'd fine with the original over clock a few times no probs, no artifacts, now its doing this?

 

Keep in mind that OC is not same as Flashing.
OC is controlled by software. The software used to overclock know how to modify the GPU files(whatever it is) well. So, it won't easily screw-up your GPU.
Flashing is controlled by software too. However, flashing is too complicated compared to OC.
For example:
OC a core clock of a GPU using a software. The software will auto-write suitable system files for the OCed core clock. So, it won't crash easily.
Flashing OC a core clock of a GPU using a software. The software will not auto-write suitable system files for the Flashing OC core clock. So, you need to do it yourself(super complicated). If not, it may easily crash/unstable.

 

I see.... but i just don't understand that it worked fine at 625 / 475 for about 4 days ... then now if i go to 500, i get artifacts

 

Well, well, well. I have no clue about it.
My suggestion is that, you should undervolt the Geforce 9500M GS instead of OCing it.
With the undervolted Geforce 9500M GS, you can overclock it like hell(probably 625/500/1500).

For your info, I got my Nvidia system files(whatever it is) corrupted. I don't know how I mess it up, reinstallation of whole drivers and all nvidia stuffs are useless. I can't install nTune due to that. Instead, I used EVGA Precision 1.8.0 for overclocking, it works like a charm(lighter than nTune). Lastly, I think it is registry problem(about nvidia corporation). Lazy tinkering around(EVGA already did it). LOL.