My system keeps on freezing up after I choose Windows Xp Operating system which is right after the motherboard checks the CMOS on startup. I was futzing around with the RAM and when I started it back up it said CMOS checksum error. I went to correct everything in CMOS which was back to the default settings and hit save and it continues. Then I selected Windows XP over a diffrent windows XP (i have two copies that I can choose from on startup) and it just freezes on the countdown till it automatically logs you in to the top selection. I cant figure out what the problem is... Anyone have any ideas?