Is it the motherboard?

Hi,

My borther wanted me to build him a computer as cheap as possible (he is 14 and has no money). So I put together a computer for him based off of the Elitegroup K7S5A (possible the cheapest SocketA MOBO ever made; 65.79 CANADIAN!), a 1600+ (my old one), and a Radeon8500/9100 Graphics card.

Anyway, last night all I could hear was this electronic humming/buzzing, and couldn't figure out what it was. The next morning it was still there, so I went to check it out. It was coming from my brothers computer. So i opened it up (the computer was off by the way), and the Radeon's fan was spinning!!!! I turned off the PSU, then turned it back on and the fan resumed spinning. It very noisy, a sort of oscillating up and down grinding noise. My theory is that the card is in fine condition, but that the cheap-*** motherboard is passing current on to the card even when the machine is off. Also, I don't think it is passing the correct voltage hence the erratic RPM changes/grinding noises produced by the fan.

I tried powering up the computer to see if the fan would then go back into normal operation. The noice was drowned out, however, by the CPU fan and case fan so I couldn't tell. I just told my brother to use it as normal, but to be on the look-out for frequently locking games/visual artifacts. If he saw them, he should shut the computer off and tell me because the card is overheating and the fan not working. I also told him to, in the mean time, turn the PSU off after the computer is off to prevent damage to fan/graphics card/anything.

So, what do you think? Is it the motherboard passing on incorrect voltages? Or is it the graphics card (maybe the graphics card is supposed to get a current all the time, just not do anything with it; I don't know)?

Thanks!

Well, I've never heard about GFX fans being on all the time! That's because they shouldn't be AFAIK. Now I am assuming, that it is a stock fan, connected to the radeon.
This shouldn't be happening. I think you should try to RMA the mobo. It may work with no problems forever, but it may as well fry your components if its voltage regulators decide to go bananas. I wouldn't take that chance

so just chuck the vid card or get a better fan. right?

Well, I'm not going to chuck the video card, because it's not me, it's my brother, and he can't afford a new one. BEsides, I still think it's the mobo. So yeah, we're going to try to RMA the motherboard, and after that, never buy a $65 CDN motherboard again!

What would chucking the video card do? It sounds like a motherboard issue. I've read the AGP slot gets current even when the system is off (but power supply turned on.) So, maybe some connectors are messed up on the motherboard, and providing power to the card at all times in a way that is lucky its not frying, but just spinning the fan.

Even with a cheap video card like that, don't risk it in that motherboard. You probably paid more for the video card than board. As someone suggested, RMA the motherboard. If it does it again, go and pick up a cheap nForce2 board (SPP/MCP boards are cheap, like 60-70 USD.)