Electrical whining noise from MOSFETs on K8V SE Deluxe

Splinter · Post by **Splinter** » Thu Jul 08, 2004 12:28 pm

During heavy CPU or USB loads, my new K8V emits a loud but almost inaudibly pitched whining noise from the MOSFET/Power Regulation area. I've contacted Asus tech support, and they say that it's EMI due to improper grounding, does this sound right to you?

I can hear it even over the fairly noise stock fan on the A64 which I havent replaced yet, it's driving me nuts!

Edward Ng · Post by **Edward Ng** » Thu Jul 08, 2004 5:09 pm

Don't worry; it's common. My P4P800 emits coil whine quite nicely when it's under heavy load from Prime95 or CPUBurn.

Splinter · Post by **Splinter** » Thu Jul 08, 2004 6:04 pm

I'm not so much worried as I want it to go away

My ears are really sensitive in that range, and it bugs the crap outta me.

Edward Ng · Post by **Edward Ng** » Thu Jul 08, 2004 6:14 pm

I can't think of a cheap solution for our coil whine problem, unfortunately. Some people mentioned putting some nonconductive material on it to stabilize the coils, but I do not know if it would be effective, and if there would be adverse effects to the operation of the board.

Splinter · Post by **Splinter** » Thu Jul 08, 2004 8:52 pm

Feasibly it could cause them to overheat...

Although it would take quite a bit to damage copper wire around a ferrite core.

Edward Ng · Post by **Edward Ng** » Thu Jul 08, 2004 8:57 pm

True; I do not know how hot they get. I am aware that the MOSFETs get quite hot, but wasn't too sure on those coils...

Splinter · Post by **Splinter** » Thu Jul 08, 2004 9:45 pm

Is it DEFINATELY the coils that make the noise?

Edward Ng · Post by **Edward Ng** » Thu Jul 08, 2004 9:52 pm

Well, it's around that region of the mainboard (open-air listening tests of my Hyper 6 testbed under load), and I am pretty confident it's not the MOSFETs...

Splinter · Post by **Splinter** » Thu Jul 08, 2004 9:59 pm

It just seems strange, because there is a similar noise that seems to come from the same area when I scroll on some webpages. Why would power regulation circuitry be affected by that?

Edward Ng · Post by **Edward Ng** » Fri Jul 09, 2004 4:14 am

I really wish I knew!