Page 1 of 1

Fixing a problematic T61p...

Posted: Tue Feb 17, 2015 11:48 pm
by Mightyena
Hi, I bought a used T61p 6457-7WG a few years back that used to be my main laptop, until I replaced it with a T420 about a year ago when it started having...difficulties. Being a somewhat sentimental sort, I decided to keep it around as a backup and just to tinker around with, and it's lasted pretty well considering it was never the most reliable thing in the world. It has however developed 2 problems that stick out most, which I'd quite like an opinion on:

- So far 2 inverters have died within quick succession (1 died, replaced it and within 2 days the replacement went too). Bad luck, or indication of a deeper problem? Is it possible that the board/screen or even something else is killing them?

- Sometimes it just loses power. By this I mean when it is plugged in or with a charged battery connected, there are no lights, and absolutely nothing happens when the power button is pressed. This usually goes away by itself if I just leave it for a day or so... My thoughts are that the only way to fix this is likely a new motherboard?

The other problems are pretty unavoidable - the Quadro FX570m puts out more heat than your average sun (it actually sometimes causes the CPU to throttle due to heating up the shared heatsink too much!), and on inspection is an 0750 chip, so is likely to die of the nVidia bug anyway, which is strange, since I was under the impression that heat killed those, and this one has been running absolutely fine at around 85-90C for ages!

It also seems to have picked up a 'phantom' wifi card... One day Windows 7 just suddenly found and installed an Atheros wifi card, and added it to the network connections menu, however no such card physically exists in the system... Odd.

Anyway, if anyone has any insights on how to sort these problems (if the only viable option is mobo replacement I may just leave it - It doesn't actually see a great deal of use these days), I'd be very grateful.

Thanks,
James

Re: Fixing a problematic T61p...

Posted: Wed Feb 18, 2015 1:34 am
by axur-delmeria
Sometimes it just loses power. By this I mean when it is plugged in or with a charged battery connected, there are no lights, and absolutely nothing happens when the power button is pressed.
IMO this goes to the "replace motherboard immediately" category, unless you're handy with an oscilloscope and have a copy of the schematics.
It also seems to have picked up a 'phantom' wifi card... One day Windows 7 just suddenly found and installed an Atheros wifi card, and added it to the network connections menu, however no such card physically exists in the system... Odd.
I think it's the reverse: there's an Atheros wifi card inside, but the system has difficulty accessing it. It actually sounds like one of the classic symptoms of the nVidia plague.

Re: Fixing a problematic T61p...

Posted: Wed Feb 18, 2015 10:38 am
by Mightyena
IMO this goes to the "replace motherboard immediately" category, unless you're handy with an oscilloscope and have a copy of the schematics.
That's what I feared... Oh well, it had a decent enough run...
I think it's the reverse: there's an Atheros wifi card inside, but the system has difficulty accessing it. It actually sounds like one of the classic symptoms of the nVidia plague.
Nope, I've pulled it apart and the only thing physically installed is the intel wifi card that also shows up in device manager alongside the phantom Atheros. Probably is still the nVidia problem though

Re: Fixing a problematic T61p...

Posted: Sun Feb 22, 2015 10:32 pm
by farmall
Easy way is wait for a cheap Intel GPU donor notebook and swap whatever is good from yours. My WUXGA T61 is made from an Intel base and a screen from a dead Nvidia unit. Takes little effort to swap.

Re: Fixing a problematic T61p...

Posted: Mon Feb 23, 2015 8:11 pm
by Mightyena
It started up again fine yesterday, with no power problems. Having said that, replacing the motherboard with an intel one is probably what I'll end up doing when I come across one very cheap.

On another point, do you think it could be motherboard/screen related that my T61 seems to go through inverters like battery cycles? :roll: I'm on the 3rd one now, after having 2 die on me within a week!

Re: Fixing a problematic T61p...

Posted: Mon Feb 23, 2015 9:10 pm
by rkawakami
It's possible that a bad/dying backlight (CCFL) or a bad connection could be killing your replacement inverters. Either that, what you're putting in there isn't the right type of inverter. To a lesser extent I suppose a defect on the motherboard could be supplying too much voltage to the inverter board but I think that it's a much smaller chance. I've personally blown up a couple of inverters by either shorting out the output or running it without a backlight connected; both were "buzz, snap" kind of failures, followed by the smell of burning plastic and the escape of the magic smoke from one or more of the components on the inverter board.