HP m7660pt won't start!! Help please...

jribeiro

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Dec 4, 2010
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Hi there!!

I have an HP m7660pt (you can view the specs here).

My problem is that when I press Power On the fans come up, I hear the fans working for 1-2 seconds and then everything shuts off... Nothing is displayed in the screen and no indication that pc really started. After everything (including fans stop) the front light remais on...

Firstly this problem started to happen once in a while and now I can't turn on the computer at all.

Already tried to unplug almost everything... Even took the CMOS batery off for a while. No luck...

You can view a video of the problem here.

Any idea of what might be wrong??

Please somebody help 'cause I'm going mad here
 

jribeiro

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You've tried swapping out the memory modules ?

Yes... I have two of them... I tried to take out one at a time and the problem persists...

If I take booth I wear beeps and then the computer shuts down...
 
G

Guest

Guest
Power supply -- have you checked the 3.3v, 12v and 5v sockets with a multimeter ?


 

jribeiro

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Power supply -- have you checked the 3.3v, 12v and 5v sockets with a multimeter ?


No.. I don't have that equipment... But I'm thinking on buying one to test out.. From what I can tell so far it can only be the PSU or the mobo.

Going for the chepeast... Do you agree? Or do you think I should proceed differently?


Thanks for the help
 
G

Guest

Guest
Depends how much use you'll get out of a multimeter -- digital multimeters are always pretty accurate but the weak point is the rotary switch range selector. Cheap ones tend to disintegrate before more expensive ones -- but you can be lucky.

If your question was should you replace the PSU or the mobo (which ever is cheapest), PSU is usually cheaper -- and will not involve reinstalling Windows !


While looking around in the computer motherboard have a look at the capacitors standing around the area of the CPU -- they can fail and the telltale sign is usually bulging of the end caps. In which case replacing caps costs pennies (if you can solder).
 
G

Guest

Guest
Just noticed you mention disconnecting the BIOS battery -- the official way to clear the BIOS (and this just might be the issue) is to move a jumper (see manual if you can figure out who made the mobo) -- dirty way is to remove battery and short the terminals of the battery holder. That should give you enough to think about -- I'm signing out now as it's past breakfast here.
 

jribeiro

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Depends how much use you'll get out of a multimeter -- digital multimeters are always pretty accurate but the weak point is the rotary switch range selector. Cheap ones tend to disintegrate before more expensive ones -- but you can be lucky.

If your question was should you replace the PSU or the mobo (which ever is cheapest), PSU is usually cheaper -- and will not involve reinstalling Windows !


While looking around in the computer motherboard have a look at the capacitors standing around the area of the CPU -- they can fail and the telltale sign is usually bulging of the end caps. In which case replacing caps costs pennies (if you can solder).


I was referring to the PSU... I've looked at the capacitors on both the mobo and PSU and both seems fine... at least didn't verified any bulging but i cant be really sure as I didn't take the mobo off and as far as I know the problem can be hidden behind the capacitor right??
 

jribeiro

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Dec 4, 2010
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Just noticed you mention disconnecting the BIOS battery -- the official way to clear the BIOS (and this just might be the issue) is to move a jumper (see manual if you can figure out who made the mobo) -- dirty way is to remove battery and short the terminals of the battery holder. That should give you enough to think about -- I'm signing out now as it's past breakfast here.


I cleared the bios as instructed by HP but the issue remains...

By the way I noticed that if I plug the power cable to the PSU the computer starts off immediatly and everytime I try to restart it again it tends to shut down more quickly (for instance the first time I turn on it runs for about 3-4 seconds, about 2 seconds for the second time and so on... sometimes on the following tries the fans don't even start)

If I let it rest for a while (without power cable) it comes back to the 3-4 seconds...

Have a nice day then... Really appreciated the hep!!

Thanks,
João Ribeiro
 

Gimp

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If it were memory fans would still be going round but you may have no signal on monitor like what you got now.

I would beg borrow an equivalent rated psu and test that if that fails then mobo likely culprit with fans stopping and power gone.
 

jribeiro

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Hi there!

I think that it will be very hard for me to get a borrowed PSU for this PC as HP use propertary hardware and I think that only their PSU fits... At least that's what I read.

I think I don't have many solutions besides buying one PSU from ebay and pray that will solve it :)

Thanks for the support
 

Gimp

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For a small charge your local computer shop will identify the problem you don't have to have it fixed by them you could then do it yourself if you are competent to do it else leave it to a qualified person.