hi i m been using window xp on my system for last five months without any problem last week i add an additional module of 256 ddr ram and installed window vista on seperate partition but of late i m getting the error bsod screen saying PFN_LIST_CORRUPT or IRQL_NOT_LESS_OR_EQUAL. Is there any solution to these problem except for reinstallation as this problem is only there in window xp not in vista