Wrong clock speed on Intel GMA950?

C

COCOViper

Gawd
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Dec 16, 2000
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Alright...I know 95% of you are going to say it won't even matter...but considering how slow it is to begin with, every little bit has to help :-P.

I've got a Dell E1505...and I know the spec'd speed of the GMA950 on my 945GM chipset is supposed to be 400MHz...but when I downloaded PCWizard (http://www.cpuid.org/pcwizard) to check the timings of the stock dell memory I saw that the GMA950 was only running at 250MHz.

So here's my question: Did dell clock down an already very slow graphics chip? And if so, does any one know how to go about getting the full 400MHz out of it?

Thanks guys
 
hmm...you think running say...Quake3 in windowed mode would let me check the 3d mode clock speed?
 
tried both Q3 and Rthdribl, and PCWizard reports 250MHz always. I made sure I had max performance settings/was plugged into the wall and I also tried starting Rthdribl first and then opening PCWizard but the result is the same.

Anyone know how to get this clock up to stock speeds? Or perhaps another tool to double check if the reading is accurate?

thanks
 
I really think that tool is simply reading incorrectly. A way you could check it, though, would be by running any of the 3dmark benchmarks and looking at the multitexturing fill rate. If it's really running at 250mhz then the fill rate can't possibly be over 500 Mtexels/sec (250mhz x 2 pipes). If it's running at 400mhz then it should be higher, with a max possible of 800 Mtexels/sec.
 
well I know the gma 950 has 2 pipes and 2 texturing units. So if its running 250MHz then it should actually be near 1000, and at 400MHz should be at about 1600Mtexels.

And 3dmark reports a fillrate of 968.4Mtexels :( Which leads me to believe the 250MHz is correct.

Anyone else have any thoughts?
 
oh it's got 2 texture units as well? Hmmm I didn't know that...I thought it was a 2x1 setup. Anyway, if it is indeed a 2x2 then yeah...looks like it might be running at 250mhz.
 
The GMA900/950 actually has 4 pixel pipelines (4x1). http://www.intel.com/products/chipsets/gma950/gma950.pdf

PCWizard 2006 shows my GMA900 running at 333MHz. 3DMark2001 SE gives a score of 699MT/s (single) and 779MT/s (multi). I think there's something wrong with more recent GMA drivers. xbitlabs had much better performance with older drivers in the fillrate tests: http://www.xbitlabs.com/articles/chipsets/display/i915g_4.html

COCOViper said:
Why on earth would dell clock this thing down? :mad:
Click to expand...
Dell didn't clock it down. It has a fixed 400MHz clock speed. The performance in 3DMark2001 SE seems to be a problem with the drivers. The misreading of core speed is a problem with PCWizard.
 
Dell didn't clock it down. It has a fixed 400MHz clock speed. The performance in 3DMark2001 SE seems to be a problem with the drivers. The misreading of core speed is a problem with PCWizard.
Click to expand...

Hmm...can you think of any other tool that will let you check the clock speed? Also, what is your GMA900 scoring in 3dmark2001 (overall)? Mines only pulling about 5000 (4993 was the highest I got with the latest drivers direct from intel....4600s with the dell drivers).
 
Oops. :eek: I was looking at the wrong datasheets. The mobile chipsets are downclocked compared to the desktop chipsets by default. The 910/915GM chipsets run at 200MHz and the 945GM chipsets runs at 250MHz. I think PC Wizard is using a fixed table for displaying Intel graphics speed, which is why it "correctly" identified your clock speed and gave me the wrong speed. You can use powerstrip to read the actual speed the right way.

I was digging into the PCI-E video device 2 registers with wpcredit and I see what's going on with my laptop, but it also applies to the 945GM: the chipsets can be used in 2 different voltages for the graphics core: 1.05v or 1.50v. At 1.05v, the core is spec'd to run at 200MHz or 250MHz (910/915GM and 945GM, respectively). At 1.5V, it's 333MHz (910/915) and 400MHz (945GT). That explains a couple of things, especially the longer than expected battery life I get from my laptop. :p

See page 207 of the 910/915GM datasheet (register F0): ftp://download.intel.com/design/mobile/datashts/30526401.pdf, or page 279 of the 945GM datasheet (register f0): ftp://download.intel.com/design/mobile/datashts/30921901.pdf

Could you overclock it? Maybe. Intel doesn't document the graphics clock PLL register (F2) so lots of luck. It's also tricky to perform the chip reset necessary to apply the new graphics clock settings. :p But even if you could overclock it, there's no way you're getting to 400MHz while the graphics core is running at 1.05v. To make things worse for the 945 mobile chipset, the version that runs at 400MHz is the 945GT which could mean no user programmable graphics clock generator (register F2 is missing from the 945GM/GT datasheet).

(edit) just to clear it up simply: all 945GM chipsets run at 250MHz graphics core speed. The 945GT runs at 400MHz.
 
heh I never even noticed we were talking about a mobile chipset here...I just saw gma950 and instantly thought of 945G. Good call pxc
 
well thats interesting....I wonder how hard it would be to transform this 945GM into a 945GT then.

Incidentally, I ran pstrip and it actually reports a 200MHz clockspeed :p fun times. Too bad its OC sliders don't work. You think just by modifying a voltage and clock speed register with wpcredit 400MHz could be pulled out? Any chance it (the clockspeed) could just be a driver setting or do you think its wired hard into the chipset itself?

I figure the difference between 250MHz and 400MHz combined with my 1GB stick that arrives next week to give me dual channel memory would probally make the difference between the current 5000 3dmark's (2001SE) and maybe close to 10,000 3dmarks. Because that is the difference between nonplayable and barely workable for quite a few games.
 
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