I have a vista home 64 computer. I have just taken out a bad ram and replaced a broken moniter. While i have had blue screens (irql not equal, pfn list currupt, page deault in no page area, system service exeception), it now just freezes after a few minutes. If i start it in safe mode then it will go for 10 to 15 minutes before freezeing. I have scaned with vipre and have found no viruses and have run chkdsk and a memory test with no errors. I need help finding why it freezes and how to fix it. Thanks for the help.