Sometimes you get a memory skip, too, during bootup. 'S caused by electromagnetic interference with the system, sometimes EM waves start bouncing around in there and when they hit a conductive object (like, say, the copper strips on your motherboard) they produce a tiny electrical charge, which the central processor can take as an error, leading it to reload things. Given the regularity of the problem and the likelihood you're computer's shielded, the emitter is probably internal- the most likely suspects being your hard drives, which are highly active during startup. In recent years computer companies have gotten lazy about this sort of thing and taken to leaving hard disks open to electromagnetic leakage. The most permanent solution to the problem is to block the EM field the hard disk produces by setting up an ionised field around the device that will absorb and counteract the offending magnetism. Basically, charge the thing. And the best way of charging a disk short of doing something stupid like connecting it directly to a wall socket is to hit it with radio waves of a certain frequency. You ever seen a metal fork spark in a microwave? That's because it's inducing a charge, which the fork, being an inert object unlike most electronics, does not retain but instead releases into the environment (rather damagingly to the microwave). So ... just do the same thing. Let me know what happens.
