I’m trying to figure what to do with random failures to boot. My old HP Presario R3000 with AMD Athlon XP-M sometimes boots, sometimes hangs with a blank screen during boot, and sometimes hangs on shutdown. After a few boot attempts it will finally boot to the GNU GRUB screen where I usually can select Recovery Mode, then select return to a normal boot, and the thing will startup and function normally. The pattern is not repeatable and seemed to start after upgrading from 11.04. Clean installs of 12.04 and 12.10 on newly-formatted hard drives make no difference. If this might be a clue, hangs on shutdown often stop at a line with: “pcmcia_socket pcmcia_socket0: cs: IO port probe 0x3000-0x7fff: excluding 0x3000-0x30ff 0x3400-0x34ff 0x3800-0x38ff 0x3c00-0x3cff”. I did try the “acpi=off” modification from 11.10 randomly fails to boot on Compaq Presario R3000 with no change in these random boot failures. Any suggestions sure appreciated.