4870x2 High Pitch Noise

I recently put together an i7 build with a 4870 x2. Everything was fine at startup and even through installation. Vista 64 runs perfectly with no BSOD/errors. I installed the latest catalyst drivers. Everytime the card goes under heavy 3D load, there is a annoying hissing/buzzing noise. The games run fine and there are no crashes.

I had a brand new PC&C 750w PSU, which I thought was the problem. I since replaced it with a Corsair 750w PSU, which I thought would solve the issue. The buzzing is still there and I am not sure if its the Video Card itself or I need a more powerful PSU.

I checked to see if it was the fans causing the noise, but infact it wasnt. The wierd noises sound like a high pitch buzz and it only seems to happen under heavy GPU load.
Anyone have any suggestions as to what could be the cause of this noise?

Specs:

Core i7 920
Nexus FLC-3000 HSF
Asus P6T Deluxe
Patriot 6GB ddr1600
Sapphire 4870 x2
WD6401 AALS x 2 (Matrix Raid 0)
Corsair 750w PSU
Sata DVD-RW Drive
Antec NineHundred Case

How does a card squel? Is it the fan?

No it is more like an elecronic squeel. The fan is perfectly fine and I have it running at 45%. It sounds like an electronic hiss coming from the Video Card. Like a high pitched buzz.

I had the same problem with a pair of HD4870s on my Thermaltake Toughpower 750 watt PSU. Anytime I'd fire up a 3D game such as Warhammer, you could hear an electronic buzz come from both cards. I ended up swapping out my PSU to a Corsair 1000watt PSU and the electronic buzz is gone. I'm not sure if it would the same fix for you, but it worked with my setup.

Mine actually has the same issue except it's really only audible when the case door is opened. I read somewhere that the noise comes from a particular electrical component on the card (no, it's not the fan), but the term for it escapes me at the moment.

Edit: OK, looks like the noise is probably coming from the inductors on the card (the coil looking dealies).

Mine does that very slightly. I didn't notice it at all with the stock cooler making a racket but now that it's watercooled, I do notice it if I'm paying attention.

I can verify its not coming from the fans since both of my ATI cards are on water.
And yes, I think its the VRU's (Voltage Regulating Unit) or the inductor as Heatsinker points out. When running GPUz I noticed 26.1A each card was using fluxed a bit during gaming, but its been stable with the new PSU.

Don't two CF 4870 video cards, draw more power then a 4870 x2?

I thought 750w would be suffecient for a 4870x2 and a i7 920 (4Core 130W).

Corsair 750W would handle the X2 without any problem.

I notice a faint humming sound in Stalker Shadow of Chernobyl during the in game menu. In all other
games It is not audible. That is very weird indeed.

Im contemplating RMAing the GPU back to Newegg. I already tried RMAing the PSU, with no luck. What do you guys think?

Mine did that until I enabled v-sync in games (or disabled can't remember), so give that a try.

I had this with my 9800gx2. RMA fixed it right up (noise cap was the problem).

I think im going to RMA it.

I've heard of whistling capacitors on mobos.
Could it be that?

I've had a similar problem. I had a HIS 4870x2 with exactly the same problem with a corsair 750w PSU. Just had the card RMA'd and getting a replacement soon. I'm hoping it was an issue with the GPU and not the PSU...I'll let you know how it went when i get my replacement.

Noise is most likely from the PSU. Pretty sure it isn't hurting anything but for some reason newer cards like to make corsair psu's squeal a bit. My guess is some cards put out an unusual amount of noise that causes a coil or cap in the PSU to whine a bit. Caps and coils are always vibrating, just that the frequency is outside the range of human hearing most of the time. My 4850 does it on my 650 tx a tiny bit, and on my old antec truepower 430 alot when I was trying to troubleshoot a stability issue (turned out to be a bum card). I happen to like my corsair warranty so I'm not going to open up the psu to try and throw epoxy/hot glue on all the caps and coils I see to get rid of the noise.

*edit: seems related to vsync, since it quiets down the noise to the point it's not noticable. I've noticed this the most in rthdribl, in window mode where vsync doesn't work, it happens regardless of framerate. Zooming in on the balls can sometimes cause it to get louder or quieter. Very wierd, but most likely harmless.

My x1800xt does it. It's still working :P

I know this is mainly for the GTX 280 but it may help you.

Yah, this issue seems to be common on nvidia cards as well. If it's really loud, I'd RMA it. Personally my card doesn't do it in far cry 2, crysis, cod4, and grid. The noise is only a bit audible in stalker shadow of chernobyl for some reason.