Any idea if computer case screws use a standard thread size, like 2-56, or 8-32? I am hoping to start work on a custom built wood/aluminum case this weekend, and happen to have a handful of Brass ...

Along with the pitch, or number of threads per unit length, thread friction contributes to the self-locking, or “non-overhauling” property of most screw threads.

I've never seen 4-40 thread standoffs (that is the size of the hold down screws for DVI, VGA, serial, etc.), but definitely have seen both 6-32 (aka hard disc screws) and M3 (aka CD-ROM screws ...