Hello Yen. I have some information that you might be interested in. Maybe you know about this already but here's what I found out on my own. You know I've been having problems activating x64 using the HP ISA file, the x86 activates fine. I know that the SLIC table should checksum to 00 and the whole ISA file should also checksum to 00. I ran WinHex on the HP ISA.BIN file included in the NISA-ALLOEM archive and the checksum is 00. I extraced the SLIC table from this file and the checksum is 86, it should be 00. I took the HP SLIC table from the "Slic tables with fixed checksums" archive and that checksum is 00. I put this table into the ISA.BIN file and corrected the last byte at 3FFh to 94h. Now both the new ISA.BIN file that I made AND the SLIC table checksums are 00. This should be correct now, right? Do you think this is the reason why x64 would not activate? I will flash my bios with the new ISA.BIN and install x64 and I will let you know. I don't see any reason why it should not activate now that all the checksums are correct.