This is a known working board, and with known working RAM, it's fine, so I doubt that there are any bad solder joints (there is a broken clip I discovered, though, but I don't see why that would cause this particular problem).

Sometimes, with the apparently bad RAM installed, the screen will look garbled during the RAM check, then produce the Sad Mac.

I am uncertain how to determine the speed, but I will try to figure it out.

c