About 4 months ago I upgraded my mac mini from the standard 1gb to 2gb and upped the hard drive to 250gb. In the process, one of the memory slots became unusable. It simply does not acknowledge any memory is in that slot no matter the size of the chip. I decided to just live with this and popped in a 2gb memory stick in the one working slot. Over the past few months I have started to notice frequent crashes. I have been an avid mac user for about 3 years now and my mac mini has been crashing on average once a day if i push it and at the very least once every other day. It completely freezes up and I have to do a hard reboot. I ran memtest and came up with 263 errors. Later today I am going to take the 2gb chip out and swap for a 512mb chip and do the test over again. If I get more errors I will assume that the problem is with the logic board and not the memory chips. Assuming the logic board is faulty, what are opinions on inserting original memory sticks / hard drive and calling up apple, telling them i have been having problems and sending it in for warranty? Will they reject it due to the obvious scarring on the plastic that shows that I opened the mini up? Has anyone here done this? Botched an upgrade and had apple fix their screw ups?