Sounds like either a bad power supply, or maybe there's a screw loose in the motherboard, causing it to short out.
Edit: Now that the fun is out of the way (read the forum description). I would take it back to the place that installed it. If you don't want to do that, you can get a nutdriver, but I can't remember the size. The problem is, all nut drivers, the wall of the driver is to thick to let it get completely around the screw. Some folks have used a grinder or dremel, to thin the wall out so it can get clearance and can tighten it.
Or, order a Glock Front Sight tool from Lonewolf, and pick up some blue loctite at the hardware store. Use the Front sight tool to remove the screw, and dab some loctite on the threads. Then tighten it back up.