Power on: Nothing but PS whine
I know this has been discussed before (early this year) but the problem wasn't fixed.
So I'm trying to power up an Intel AL440LX mobo with a P2/300. Put in just a stick of RAM (tried different ones too), keyboard, and an MGA Millenium PCI. Didn't really know what to do about a power button but took a button off another machine and hooked it to the two PWR ON pins on the mobo. The power supply is a 200W Dell that I know works fine (I also tried a duplicate of it that previously worked also).
Plugged it in, nothing happens but it starts up a really high pitched whine like a capacitor. Pushing the power button does nothing. I tried another 200W Dell PS and the same thing happens. I notice that when I unplug the PS, the whine quiets and stops within 15 seconds; unplugging the main PS to mobo connector cuts off the whine but it continues when you plug it back in, even if the PS is unplugged.
It does the exact same thing with an old Acer motherboard, too.
I have 2 ideas:
1. The mobo isn't fully grounded (do I need to put a screw through every metal surrounded hole on the mobo into the case?).
2. The weird looking extra plug on the Dell PS means something. (pic attached)