A31 Boot Problem

[Harryc]

I am working on an A31 that intermittently does not boot up to BIOS. I am not running a hard drive yet. When it does boot up it sometimes locks up. It is not a keyboard, ethernet card, modem card, drive, RAM, or AC adapter problem (all swapped or removed). All lights come on and sequence normally, but there is no POST beep...even when it works. If I get it to boot and go into BIOS, I can make changes, and it freezes after awhile....sometimes. Battery installed or removed, AC adapter installed or removed...doesn't change the overall symptom. Ideas? I am thinking loose GPU or a CPU problem.

[Harryc]

Interesting development - I unhooked the Internal LCD and hooked up an external through a dock. In this configuration the machine boots and works normally. So, I am looking at something in the LCD intermittently shorting or not providing signal or power. Inverter? Cable? Shorted CCFL?

[SMA]

Try with both LCD and external monitor simultaneously. See if the machine continues on the external monitor after the lcd has frozen.

[Harryc]

Tried that, and they both freeze at the same time. I am using an external USB keyboard...no response. Also, the machine continues to freeze with the Internal LCD disconnected. On to the CPU ...

[ajkula66]

I'll say bad VRAM...parted one with the exact same symptoms a month ago...

Hopefully I'm wrong and it's the CPU...

[Harryc]

George, I think you hit the nail on the head. I changed the CPU out and it did not fix the problem.

[RealBlackStuff]

Contact the guy in this post: http://forum.thinkpads.com/viewtopic.php?f=5&t=81654
He needs A31 mobo-work done, maybe one of you walks off with a working A31.