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FAB
10-01-2007, 01:00 PM
Afternoon all

I have been working on 20-odd IBM Netvista (P1.8) desktops, just going through and reimaging etc to get them ready to be sent out as loaners.

However, 4 of the machines refuse to boot. With no HD, CD or cards (other than video) the power supply fans won't turn, no power to unit (althuogh LAN lights on MB on).
But1 If I remove the 4 pin connector for the CPU (yellow/black wires) and then plug the cable to the MB from the PS, the fans go but nothing else (no power to CPU). Plug teh CPU square connector back on to MB, then unit doesn't switch on, or fans go for 1/2 second then stop.
Have tried differnet PSs or course, no difference.
One one unit, I disconnected PS, lpugged MB connector on first then CPU power conncetor, and it worked. Thought I had it solved. But this hasn't worked for the remaining 4 PCs.
Out of desperation replaced RAM & bios battery, no difference of course. Have tried multiple power cables and points.

Ideas?
Cheers in advance.

SurferJoe46
10-01-2007, 01:05 PM
I know a guy who specializes in them...PM for an address...OK?

FAB
10-01-2007, 01:10 PM
I know a guy who specializes in them...PM for an address...OK?

Cool as, thanks.

gibler
10-01-2007, 01:12 PM
Bad motherboard capacitors ??

FAB
10-01-2007, 01:16 PM
A possibility - but these units were running before they were replaced...in saying that, I've had 2 other PCs here blow up on me, capacitors shreiking in a death call...scary when you are right next to it!
But this could be something I can loko at (or dump them if that is the problem).

SurferJoe46
10-01-2007, 01:19 PM
What position is the 120/240 switch in?

OK..just a thought!

FAB
10-01-2007, 01:22 PM
Yeah been down that road, all on 230. All connectors in the right way, everything looks good.
I wouldnt worry if it was only one, but 4 machines? Must be (surely) a common IBM MB fault, but have googled with no result.

SurferJoe46
10-01-2007, 01:58 PM
Did you get anything back from my old buddy Ross?

Speedy Gonzales
10-01-2007, 02:07 PM
A jumper maybe missing.

I know with some mobos ie: The CMOS jumper.

Did u take the jumper off any of these when u replaced the battery?

If u take it off and put it on the other set of pins to reset it, if u don't put it back on the right set of pins, it wont boot either. Or if u leave it off altogether.

FAB
10-01-2007, 02:50 PM
Thanks guys - I think Gibler was right - I see slight bulging in certain capacitors on the MB...must be a common fault I guess after all. Needed to put my glasses on for a close up.

gibler
10-01-2007, 08:55 PM
Thanks guys - I think Gibler was right - I see slight bulging in certain capacitors on the MB...must be a common fault I guess after all. Needed to put my glasses on for a close up.

I've seen the problem numerous times at work. One user did have a m/b where the top clean blew off a capacitor and I was told the bang was quite loud. :lol:

Google reveals that some netvista models had issues with their caps.

george12
10-01-2007, 08:58 PM
Where do you live? I know a guy in Wellington who will replace the caps in a board for $30-40 per board. It definitely sounds like caps to me.