Random beeping

[rhecl]

Hey all!

My brother's computer is making some random beeping sounds lately (it's like the motherboard's speaker's sound). It only occurs while he's playing games though. And it doesn't even happen with all games, but just some, which seems awfully strange to me.
It usually starts like a minute or so after he starts playing and it doesn't stop till he returns to the desktop (the funny thing is that even a alt-tab switch to the desktop stops the beeping, but it starts again if he returns in-game). I didn't notice any particular pattern in the beeping, it just seems random.

Any ideas?

[rhecl]

Oh and sorry if i put this thread in the wrong section. Wasn't exactly sure where to put it.

[Salem]

Is it a homebuilt machine?
Has it been overclocked or otherwise modified for extra performance?
Have you searched for "<name of motherboard> + beep" ?
Are all the fans working (at full RPM)?

Some games will stress the machine quite a lot, so my guess is that it's some diagnostic beep caused by running the machine too close to the edge.

One thing to try easily is memtest86
http://www.memtest86.com/
Just create a boot disk/cd, then let it run overnight or something and see what it says.

[rhecl]

Yes it's more or less a home-built machine, not overclocked, gotta check if the fans are at full RPM and yes i've searched for problems regarding this specific motherboard.

Regarding memtest... I left it running for 4 hours when we first built the computer, no problems.

[Salem]

It's probably a good idea to run it again.
I recently had a machine that was solid on memtest in the beginning, and got worse and worse from power up over a period of time (it would eventually warm up enough to be useful). But eventually, it became useless at any temperature :(

Do you have anything to monitor core temperatures?

It might be interesting to try something like this as well.
http://www.playtool.com/pages/prime95/prime95.html

[rhecl]

I'll do some stress testing again then. But i'm not so sure that stress is the problem... For example: a game like Crysis which pushes the PC to its limits doesnt make it beep, while another less demanding game does. And it completely stops with just an alt-tab to the desktop.

Well anyway, like i said, ill do some tests later on and will report if i get anything.

[rhecl]

Right, I did a memory and CPU test. No errors. Another thing we noticed is if the beeps start, they just go away after a few mins.