fails with CD tray empty and all usb ports empty?
sure there are 20 causes of PC freezes.. this is not new ground.
Gee wiz leave the huge battery out and run on AC power. only
using only the AC >DC powerpack, well doe it run correctly now?
C14 says (age)
1999 PC made , so is 18 years old then,.
no battery lasts 18 years ever., for sure the coin cell CMOS battery is dead, and when that happens BIOS goes MAD (as a hatter)
key word CHAOS. error 251 (post) is this. and 260 and 270. too,.
My gosh vast IBM documents exist on this PC (IBM is BOSS, PRIME in this quality metric)
the battery is page 75 here.
https://www.dlmanuals.com/manual/ibm-2626hnu-thinkpad-390x-2626/user-manual/75?keywords=rtc#manualwrapwrap
failure #3 of 20.
is bad HDD, we must test it next running HDD tests on a good 2nd PC.. if OS on bad PC is dead.
failure #4 bad power pack. AC to DC fails to run PC with old useless now, 18 year old huge battery removed;
full stop. have up to 16 more to go, parts inside bad.
end relic PC post.