8600GT - flickering/wavering display

[phoenix198]

I seem to have a problem with an XpertVison nVidia GeForce 8600GT 256MB DDR3 PCI-E graphics card I've just installed - got it from Aria about 4 days ago.

Symptoms are as follows: flickering/wavering of screen image in top 30mm (approx) of screen area under Windows Vista Home Premium 32-bit edition using latest nVidia drivers on a Dell 2407 WFP LCD screen at native (1920x1200 x 32-bit) resolution. This is persistent from first boot-up (I've also seen it intermittently on the system BIOS screen) and is present on Windows desktop (aero enabled) or with applications switched to full-screen mode.

Before I start the RMA process I thought I'd better do a quick numpty check on myself, so grateful for any thoughts on the following:

- nVidia 8600GT doesn't require a PCI-e power connector and draws relatively low power. Yes?

- My PSU is a 350W no-name that came with the base unit concerned (an emachines E4264), so I should be OK for power.

- The fact that I have noticed the anomaly on a BIOS screen indicates to me that it isn't a driver problem. Right?

Thanks in advance

[vinnyT]

Try (stress)testing your card with this free utility, System Utilities, Benchmarking. Stress Testing + Benchmark + 3D Screensaver!. It should show if your have a problem with the gfx card (it sounds like it could be the cards memory that is at fault.)

Have you tried reseating the card (and making sure the connectors are clean, and intact)?

[da_ging]

have you done the auto adjust on the monitor since installing the new card? as it sounds like the monitor is simply not adjusted to me

[stevie lee]

Check the cable from graphics to the monitor, look for bent pins on connectors or kinks in the wire - faulty cable. If its a dvi cable, are you sure its a dual link? (don't know the full details about dual link, but do know that above certain resolutions you need a dual link to display properly.)

[phoenix198]

have you done the auto adjust on the monitor since installing the new card? as it sounds like the monitor is simply not adjusted to me

Yup, done that one Several times

Forgot to mention, monitor is connected via a VGA cable to a Belkin four-port KVM switch and by VGA cable onwards to the monitor. All cables are sound and securely attached and, worthy of note, the previous (supplied) graphics card (a 128MB OEM nVidia 8300GS) did not exhibit the symptom

[phoenix198]

Check the cable from graphics to the monitor, look for bent pins on connectors or kinks in the wire - faulty cable. If its a dvi cable, are you sure its a dual link? (don't know the full details about dual link, but do know that above certain resolutions you need a dual link to display properly.)

Thanks or your response however see reply above.

[phoenix198]

Try (stress)testing your card with this free utility, System Utilities, Benchmarking. Stress Testing + Benchmark + 3D Screensaver!. It should show if your have a problem with the gfx card (it sounds like it could be the cards memory that is at fault.)

Have you tried reseating the card (and making sure the connectors are clean, and intact)?

Thanks for the link - I'll try that although like you, my suspicions lie with the card's memory. Hadn't thought about reseating the cad so I'll try that too.

[phoenix198]

Try (stress)testing your card with this free utility, System Utilities, Benchmarking. Stress Testing + Benchmark + 3D Screensaver!. It should show if your have a problem with the gfx card (it sounds like it could be the cards memory that is at fault.)

Have you tried reseating the card (and making sure the connectors are clean, and intact)?

Unfortunately the app at the link you gave is only good for DirectX 9 - think its intended for XP systems or older

[vinnyT]

Unfortunately the app at the link you gave is only good for DirectX 9 - think its intended for XP systems or older

Sorry 'bout that, hadn't realised it was xp and before.

You say the monitor is connected to a kvm, does the same fault occur if the monitor is connected directly to the gfx card?

[phoenix198]

Sorry 'bout that, hadn't realised it was xp and before.

You say the monitor is connected to a kvm, does the same fault occur if the monitor is connected directly to the gfx card?

I'm pretty confident about the KVM's performance 'cos the two other PCs shown in my sig are linked to the same monitor through the same KVM, so I know it can handle the signal/bandwidth (do I mean bandwidth?). I've even tried swapping round the various KVM VGA cables with no success

Think I've exhausted all the potential home cures and numpty checks and I reckon your diagnosis of a memory problem should well be correct. So I think I'll take the RMA option.

Thanks to all for help and advice.

[RCG_Bex1]

Unplug teh KVM at both PCs. Power both off. Then re-connect. Our KVM's always got really fussy on gaming PCs. Could be the card is faulty though...

~Bex

[phoenix198]

I RMA'd the card to Aria who acknowledged that it had a "technical fault", and after a bit of a delay received a replacement. Would you %$*@# believe it - the second card has exactly the same fault! Tried it on two PCs with and without the KVM in the card to monitor pathway with the same result.

I've just RMA'd the second card now and requested either a refund or a trade in for another make/model of 8600GT.