FSB vs. graphics performance

Inquisitor

Inquisitor

Inquisitor

Soldato
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I've got my E6400 clocked at 3.2GHz atm (been playing with it all evening and settled for this). I've done about an hour's stress testing in Orthos with no errors and everything seems fine.

The problem is that it seems to have screwed up my graphics card's performance. I tried benchmarking my computer in 3DMark06 before hand with a slightly OCed FSB of 300MHz and got about 9300, but then tried again with 400MHz FSB and got only 4400 :confused:

Also, the FPS counter in ATITool went through the floor with the higher FSB (430 FPS average compared to 1100 with lower FSB).

The BIOS settings are identical apart from the FSB in each case. The guide I was using for overclocking was this one:
http://forumz.tomshardware.com/hardware/Core2Duo-Overclocking-Guide-v1-ftopict197995.html
I'm using all the settings specified there including voltages (though I wasn't sure about the southbridge/vICH voltage it specifies there... my motherboard has these as separate options).
Here are some screenshots so you can see what's going on...

300MHz:
http://imgplace.com/directory/dir1729/1177370089_7773.png

400MHz:
http://imgplace.com/directory/dir1729/1177370088_3009.png

My hardware is:
E6400
P5B vanilla
BFG 8800GTS OC
GeIL PC 6400 Ultra Low Latency

Can anyone shed any light on this? :(
 
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paul_64l said:
can you adjust your pcie lane?
Click to expand...
Is that PCI-E frequency? If so; yes, it has a max of 150MHz on my board.
paul_64l said:
also try your ram at 1t it can make a good diffrence
Click to expand...
OK I'll try that.
edit: how do you do this? I can't see the option in the BIOS :o
 
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As far as I know you cannot change the Command Rate on Intel boards. Having said that, I am fairly certain CR isn't entirely important in C2D systems.
 
FSB wont have done this.

I get 400fps with a 6800gs & 3.4ghz with ati tool. I dont think its so great with nvidia cards as its caused me some problems with graphical corruption in the past.

3dmark 05 and 06 is 6000 and 3000 respectively.


Changing the FSB might have changed NB timings but it shouldnt halve your score.
 
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Is your graphics card getting enough juice?

Overvolting the other components could be putting a strain on the PSU and therefore affecting its supply to the GPU. I heard of some AGP cards reverting to 1x instead of 8x when they didn't get enough power - dunno if its the same with pci-e.
 
My PSU is a Corsair HX520... that should be solid enough shouldn't it? The HX series features load sharing between rails, and in any case, the PCI-E connector is coming straight out of the PSU, not connected to anything else on the way.
 
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I syour PCIE slot still running at 16x? On my P5BD, it drops it down to 1x crippling my graphics performance when I up the northbridge voltage to 1.5!
 
Street said:
I syour PCIE slot still running at 16x? On my P5BD, it drops it down to 1x crippling my graphics performance when I up the northbridge voltage to 1.5!
Click to expand...
How can I tell what speed it's running at?
 
Street said:
I syour PCIE slot still running at 16x? On my P5BD, it drops it down to 1x crippling my graphics performance when I up the northbridge voltage to 1.5!
Click to expand...

Was this dropping it down to 1x while in games/3d apps or everything in general ?
 
1177424842_7256.png


There's the reason :p

Is there anything that I can do about this other than lowering the FSB? The NB voltage is on auto, FSB termination voltage is 1.4V, vDIMM is 2.1V.

Edit: fixed! :cool:

3rd post from the bottom:
http://forumz.tomshardware.com/hard...-horrible-performance-help-ftopict232662.html

Just upped the PCI-E frequency from 100MHz to 105MHz and I'm back at x16!

Getting 10500 in 3DMark06 now, thanks all :)
 
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