PC help required
 

Morning all,

Well started moving house yesterday and have the first casualty.

My PC travelled upright in the boot of my car. Now it doesn't switch on. When I plug it in the power light on the back flashes rather than stays on. I assume it's getting power. I've taken it apart and everything looks like it's seated correctly and no obvious cables are unplugged.

Any idea's? Would somewhere like PC world be able to fix it or is it justmore coste ffective to buy a new one ( it's a P4 3.2GHz).

Matt.

Ideally you need to get the power supply checked first but if that doesn't yield anything positive examine the motherboard and ensure that any cards have not worked loose in their sockets and that all the memory modules are secure. Ensure that the power connectors to the motherboard are also secure, gently push down on them rather than just visually look.

If the power lead plug is not a moulded type open it up and ensure that none of the wires have come loose and change the fuse (3 or 5 amp) as a precaution.

could even be a jumper dropped out

well I think the PSU has given up.

If I buy a new one do i have to solder in all those wires? If I do I'll just buy a new PC!

No, its a standalone unit with molex ends.

Basically 3-4 phillips screws on the back of the case to hold it in place, undo them, after first disconnecting all the peripheral wires from the hard drives, cd drives etc. Next you have a couple of plugs to disconnect from the motherboard with a bit more care, as these may have clips on one side.

First take out the long 20/24 pin molex from the board, then the 4 pin molex from next to the CPU.

Then pull all the cables and the PSU throught the side of the case.

Reverse all the above to install the new one.

:)

Whatever you do, don't get a Jeantech psu from PC World, like my mate did.
I have heard quieter garden strimmers.

MAJOR NOTE OF CAUTION - IF THE MACHINE IS MADE BY DELL IT MAY NOT USE A STANDARD POWER SUPPLY. If its a Dell, you MUST check, as the non standard power supplies use standard connectors....the result is very nasty if a new standard PSU is connected to a computer that expects a Dell specific one. :eek:

It would be a shame to start and splash the cash when you do not know what is wrong. Ideally you want a mate with a compatible spare PSU to hook up to the machine to see if that solves it.

If you do need a PSU, Enermax, Antec or Seasonic are good (among others). Seasonic are amazingly quiet and well built, but hard to find. PSU is the most important part of your system, buy a poor one and it can really cost you. All PSUs have the potential to fail with lots of use and time, the best ones generally do not take out the rest of the machine with them when they pop. If its less than £30 its not the best. If its both cheap and has a high power output claim just avoid it.

Matt,

Does it beep when you try to power it up??
Or does the power light flash??

Usually will tell whats wrong with it when it runs the POST.
(Power On Self Test)
i.e count the beeps (short and long) or count the flashes..

Worth looking on the manufacturers website as they normally have this info in their support pages.

Mel.

Got a new power supply - still won't boot. Now it comes on for a second or two then switches off.

No beeps flashes etc.

I've unplugged the HDD, CD DVD etc. So it's just the mohterboard and fans. They all start but then it switches off. Won't switch on again unless the power supply is off then on again.

I've had the RAM out and back in agin, tried both chips 1 at a time.

Pub now I think.

Thanks for the replies so far.

Incidently it's an HP t461.

did you try resetting the CMOS ? the only other thing I can think of would be the heat sink not sitting correctly, the Proc getting hot would cause the board to shut down like it is !, try taking the heat sink off, clean and apply ther paste and resit it

Pimmo's idea on the Heatsinks is a good one, also make sure ALL fans are spinning up. As if a fan fails to start, it may emergency shutdown too.

I think you have to look at the possibility of a short somewhere too. If you have managed to fit a new PSU, I would honestly take the whole thing apart. Dissassemble as much as you possibly can, and then make sure that something has not dropped into a part of the case it should not.

A single errant screw could have fallen behind the motherboard and be shorting it to the case as an example (that little trick blew a mobo of mine a year ago).

I am clutching at straws, but if it worked before the move, its worth pulling it apart and just checking everything. Failing that, at least you may have learned something :)

where are you matt i'll take a look if youlike