BleepingComputer.com: Laptop will not start after MoBo replacement

I have a Toshiba Satellite A75-S226 laptop. I replaced the motherboard, and now when I push the power button the cpu fans start and run for a few seconds then shut off. No POST, no HDD activity, nothing except the power light. The old MoBo had a defective power/battery charging circuit, but it would at least boot up and run. So I tried putting the cpu back in the old MoBo and it is now acting the same way. Is it possible that I have damaged the cpu? What else might cause this kind of problem?

Thanks for the help!

Some motherboards wont power up without CPU. You should clean the contacts of your CPU chip and make sure it is seated as it should.

Thanks for the suggestion. I have cleaned the contacts, and it appears that the cpu is snug as a bug. Still nada.

Any other thoughts? It's looking like I'll have to replace it.

Hello and welcome to Bleepingcomputer.

First a link to your owners manual in pdf format. http://www.csd.toshiba.com/cgi-bin/tais/su...mily=1073768663

That link also has other support information that you could use.

It is to my understanding, you dismantled this laptop to replace the main-board.

In rebuilding the system, did you take extra care to recheck those ribbon wires with the ZIF connectors to be sure everything is snug and making a full connection?

Laptops are one tedious device to assemble and it doesn't take much for one of those ZIF connectors to pop open breaking the connection.

I don't really think the problem you had with the other board may have caused the CPU to be fried. Or if it did, there had to be a serious short circuit somewhere.

Hope this helps.

Thanks for the reply.

I took it apart and booted it with everything disconnected...just MoBo and memory, removed from the casing. I still get the same result. Heatsink fans run for 4-5 seconds and shut off. I don't hear anything from the processor.

I agree that the old board probably didn't do this. I'm guessing I damaged it in the transfer, although I think I remember being careful.

I'll take a look at the manual and see if there's any help in there.

Any other long shot ideas? I'm googling cpu's for this guy next.

Well there is the possibility the motherboard came with a defect.

I would think it came to you with some sort of warranty, is this correct?

If it did, I would RMA it and get a replacement with another one, if that's possible.

Bruce.