I'm up at 2am because my computer is down. Help me get it to boot!

August 7, 2008 11:07 PM

My PC was working fine until tonight. I rebooted to fix a BIOS setting (to enable the onboard Ethernet port) and since then it won't boot properly anymore. The PC POSTs fine, keyboard is initialized, I can enter the BIOS setup fine and make any changes I like, then save them. After that, the screen blanks and I'm left staring at a blinking cursor in the upper left corner. Nothing happens. How can I troubleshoot this and fix it?

Keyboard is now nonresponsive. As far as I know the PC is not even trying to boot. If I hit "F9" to select my boot device, it doesn't show me the boot device screen. Every time I boot, same problem.

This is a 1 year old PC assembled from parts. Biostar TF-7025-M2 motherboard, AMD Athlon 64 X2 5000 dual core processor. 3GB RAM, Antec 350 power supply. Onboard video. Maxtor SATA hard drive. Panasonic DVD-writer. IBM keyboard. I've disconnected everything else. I'm running Ubuntu 8.04 on the system. GRUB should be loading from the MBR on the hard drive and displaying options, but it is not.

The BIOS settings include a built in burn-in-utility (memory tester) which I have tried enabling. It won't run it.

I've tried booting from the hard drive and booting from several different rescue CDs - Ubuntu Live CD, Ultimate Boot CD, with no success.

I've tried clearing the CMOS via the internal jumper. CMOS is cleared but this doesn't solve the problem.

I'm thinking that this could be:

a) bad power supply (can run BIOS but can't boot?)
b) bad motherboard (but wouldn't I get some other indication of a problem?)

Any suggestions how to troubleshoot? I don't have a spare power supply or motherboard to swap in, unless I'm willing to cannibalize my Windows PC (can't do that!)

posted by dudeman to Computers & Internet (6 answers total)

Can you swap out memory?
posted by Blazecock Pileon at 11:15 PM on August 7, 2008

Yeah, pull all of of your DIMMS except one, then swap them out each for another and see what happens.

Unplug any USB devices. Yank any extra cards and devices, etc.
posted by wfrgms at 11:33 PM on August 7, 2008

Oh yeah, cycle the psu by pulling the cord and letting it sit for 30 (longer won't hurt) seconds or so. If you can get back into the BIOS load the safety defaults.
posted by wfrgms at 11:35 PM on August 7, 2008

Response by poster: Thanks for the suggestions. I have unplugged all extraneous devices, removed all PCI cards, power cycled the PSU, loaded the default settings numerous times. I've even cleared the CMOS by using the jumpers on the motherboard. No luck. I can get into the BIOS but it won't go any further. I haven't swapped out the memory because it does pass the bootup tests. My next step is to remove the power cord and CMOS backup battery for 10min and see if that helps.
posted by dudeman at 5:45 AM on August 8, 2008

it could be a bad keyboard- is it PS2 or USB? PS2 keyboards can cause hangs in rare circumstances. Try swapping in a new one or booting without.
posted by jenkinsEar at 6:47 AM on August 8, 2008

Response by poster: Solved the problem!! (sort of.) Turns out that it wasn't enough to disconnect my hard drive data cable, I had to disconnect the power cable as well. Once that was done, the computer boots fine off the CD-ROM. So now it's on to discovering the root cause. Fried hard drive? Marginal power supply? We'll see. Thanks to all who responded.
posted by dudeman at 8:08 AM on August 8, 2008