In my situations, incompatible memory usually posts a 225 or 221, but hard to say what's happening here. The 165 comes up usually because the .adf file for an installed adaptor card is missing. That will need to be cleared before the computer will boot from the hard drive. The P70/75 had issues with the floppy drive since it's mounted vertically but hopefully wont be a problem here. try using a cleaning disk on it. goto http://members.aol.com/mcapage0 choosing the PS2 area and download peter's adaptor card ID disk. any ps2 should boot that disk. Another thing i've noticed is dont access newly created reference disks on win9x machines. Ive discovered that sometimes doing a DIR on them renders them unbootable for some reason. have fun with that P70. it's a neat machine. www.nothingtodo.org In a message dated Wed, 21 Jun 2000 4:34:31 PM Eastern Daylight Time, "Mark Gregory" &lt;mgregory(a)vantageresearch.com&gt; writes: << -----Original Message----- From: Joe &lt;rigdonj(a)intellistar.net&gt; To: classiccmp(a)classiccmp.org &lt;classiccmp(a)classiccmp.org&gt; Date: Wednesday, June 21, 2000 1:35 PM Subject: POST code for IBM P-70 does According to my references: 221 is a ROM to RAM parity error on the System board. Has someone perhaps put non-parity SIMMs in that P70? 165 is a Configuration error. Try setting the date and time and running the System autoconfiguration. I would try putting known good parity SIMMs in the P70 and then try to run the Reference and Diagnostics disks again. Cheers, Mark.