DG35EC Intel Mainboard PCI Express Problem

[incendiary]

Hi,

Got a weird problem with this motherboard - intel core2duo cpu and jetway 9800gt graphics card.

Sometimes the BIOS will read the PCI Express Lanes bandwidth as 2x and others as 16x. When it is in the clients computer, mostly it is 2x. This makes the card literally 50% slower (3dmark06 score from 11000 to 6000) and I cant yet seem to figure out what the problem is.

Suppliers couldnt find a problem with the card, and everything else i do works perfectly - in fact i got it now and i cant get it to read 2x anymore except once this morning when i had a P-ATA cdrom and hdd plugged in, but now it keeps reading 16x.

The motherboard works perfectly otherwise, except for this problem, and before i send the motherboard in and wait a month for a reply, i was wondering if it is a configuration problem - or if anyone has seen anything remotely similar with other boards / configurations ?

PS : tried other mem / hdds / dvdroms / motherboards - cant find any problems except when client has this computer and his IDE hdd and cdrom and sata hdd are plugged in, with brand new mem, cpu, 9800gt and this motherboard.
It will seldom run normal speed, and mostly slow. He complains of slowdowns in windows, and sometimes not even responding, requiring reboot - but i havent seen this yet.
Anyway, suggestions welcome

Eric

 

[tcsenter]

Latest BIOS?

Latest NVIDIA display drivers?

Windows XP

Vista 32-bit

Vista 64-bit

Is he connecting the aux. PCI-E power cable? Is the PSU adequate enough to provide stable power on this connector rail?

 

[incendiary]

Yeah, latest BIOS fixed the CPU temperature error, but not much else

latest drivers - new install of winxp pro - power cable is connected (wouldnt show anything otherwise) and im not sure about the PSU - he has a 500W and i am testing with a 400W.

Maybe the card is getting too hot ? Maybe not ... Ive got his in my computer (with a Zalman CPU cooler) and the card doesnt get hot at all ... however there are problems booting. SOMETHING must be wrong somewhere, but it looks like some little problem manifesting strangely ...

Unfortunately, about 10% of all items i buy here are faulty in some way or another this one has me stumped (for now!) and i still dont know why the intel mobo is reading sometimes as pci-e lanes 2x and sometimes 16x with that 9800gt ... i would cold-start and the BIOS shows 16x - i boot into winxp and restart and the BIOS shows 2x ... my X1900XT in place of it always showed 16x ...

Now to get the supplier to admit there is a problem ... hah

 

[Mondoman]

Sounds like a faulty graphics card. You moved the graphics card to a different computer and that computer now shows some problems, so it's clearly a problem with the graphics card. A problem with the graphics card could cause it to sometimes only use 2x lanes and sometimes the full 16x lanes.

 

[incendiary]

That sounds right ... i changed the power supply to another 400w , and got it to boot reading 16x lanes - benchmarked it to death , and got the proper speeds. rebooted ... 2x.

turned off computer, restarted and 16x again. swapped to the other 400w power supply, and couldnt get it to read 16x again ... 2x all the time. literally halves the 3dmark06 benchmark from 11000 to 6000.

now to convince the suppliers who have already given me a work-note saying all is okay that there ACTUALLY is a problem ... fun times.

thanks for the help

 

[tcsenter]

You still haven't eliminated the Intel motherboard, or have you? Have you tested his 9800GT on a different motherboard?

If the 9800GT is working fine on a different motherboard, it suggests the 9800GT is fine. The motherboard and card could both be non-defective, there is just some BIOS glitch that occurs with this particular hardware, possibly even some contribution from a flaw in Jetway's VGA BIOS.

 

[incendiary]

the 9800 will sometimes boot on my biostar motherboard, but mostly it just resets before initializing the display ... if i come back 30 mins later it will most likely have booted, and if it does the card works fine , otherwise it wont boot at all ...

have also learned that these intel dg35ec mobo's have some weird glitching on the onboard analog display and not the dvi display (prob nothing to do with this - another client was moaning about poor quality display since the upgrade

maybe i should just stick to the asus intel boards after all ...