Ok, finally made some real progress. I eventually removed a stick from the third slot and had the other three up and running. I ran memtest for a while and went to sleep, came back the next day to check it and the test had run for 14 hours and no errors occured! So it seems the third slot was causing the errors, and I noticed something about it also, it had a little speck of fluff down in the slot, so I removed that and I am running all four sticks again to see if an error still happens, whether it was the speck or the slot is shot, either way the problem was happening in that slot.
Thanks, I never would have gotten this far without a point towards the memtest software.