Clicking noise with p5n32-E SLI Plus

[ACiDuS]

Hi, I dont normally ask for help with PC stuff but I've been utterly stumped by something in the last couple of days.

I recently build a PC, using this mainboard and two 6800GT cards in sli..only to find that when used in 3D games a strange clicking noise comes from the gfx cards.

I figured this was one of the fans going, so I took them out and tried them individually. Each of them on their own can run for hours without a peep, so figuring it was just one of those weird 'new pc' things I put them back in, still no noise..yet as soon as I re-enabled sli mode, and put a 3D game on, click click click click click.

Any ideas what this might be? Its driving me nuts.

Full spec:

Core2 Duo 2.2ghz
2ghz OCZ DDR2 ram
Western Digital Caviar Sata
Vanilla CDROM
Two 6800GT gfx in SLI.

[peterb]

It is definitely coming from the cards themselves? Both? - or just one?

[ACiDuS]

Fairly sure its coming from the Cards. Its a fanless mobo and I've replaced the CPU cooler already.

When not running in SLI, the noise doesnt happen at all. I've tried both of the cards running on their own, and they work just fine.

Its hard to tell exactly which card it comes from, but it appears to be whichever one is in the primary slot at the time.

[peterb]

I was wondering if it was some form of electical interference coming from the built in speaker.

[Splash]

It's definitely not coming from the PSU (I'm just thinking of the extra load when gaming in SLI is all)?

[ACiDuS]

The PSU has been running an SLI rig using those same cards for about a year without issue.

I was wondering if it was some form of electical interference coming from the built in speaker.

Nah, its not a speaker noise, pretty sure on that.

I did something a bit stupid, I put my finger on the gfx heatsink when it was clicking(wondering if the thing was overheating), the clicks went faster for a second then stopped entirely. Still comes back eventually though.

[Splash]

The PSU has been running an SLI rig using those same cards for about a year without issue.

This much is clear, however as with most things a PSU can degrade over time - the PC was running fine until this fault developed after all. That said, it's starting to sound like it could be the bearings in the cooler of one or both cards after your last post.

[ACiDuS]

Its a rebuild, the new components are the motherboard and the CPU.

Every part of the system runs fine (on either card) until SLI itself is enabled, and then this clicking starts. It still runs in SLI, and does get a performance increase, but the constant clicking is mind numbing. The fact that the clicking stops when I put my finger on the gfx heatsink tells me its not a power issue, but I dont see how it could be a fan issue either since both the cards can run the system perfectly when inserted solo.

[Splash]

Sorry - it seems I misread. The clicking stops when you touch the heatsink, not the fan? Is this with you putting pressure on the card at all?

[ACiDuS]

Sorry - it seems I misread. The clicking stops when you touch the heatsink, not the fan? Is this with you putting pressure on the card at all?

A tiny bit of pressure, not a lot.