My E55 has served me faithfully for about three years, but lately it will only stay powered on for about five minutes at a time before powering off, thus rendering it un-usuable. I've switched power leads and sockets but it's always the same. I guessed it might be an over-heating problem, so I opened it up, vacumed (sp?) all the dust out and re-positioned it so there's nothing nearby to restrict the vents, but no improvment. Anyone got any thoughts what's causing this? Is there a heat-sync or something involved that might have gone that needs replacing?

EDIT - just found a thread that refers to a similar but not the same problem. I suspect that's probably the cause of mine too, but if anyone's having this specific issue, perhaps they'd let me know what, if anything, fixed it.

Hi Gashead, this is a common problem, I tried to find an earlier thread but failed, it sounds like the psu failing, if Gavtech comes on line he will be able to give you details of how to rectify the problem.
Dave

Is it going into "Self Check"? If so it's probably the PSU voltage regulator failing. Check out the E85 threads on the AV forums the E55 and E85 have a similar PSU and same issues.

Here is the link to the thread on the AV forum. There is also a link in there which guides you through buying the part and replacing the VR.

http://www.avforums.com/forums/showthread.php?t=385965

My E55 machine developed the same problem.

No, it's not going into self-check, at least not excessively. I power it on and it does it's standard self-check thing, but that only lasts about 30 secs or so then it comes up normally, yet about 5 minutes later it will power straight off. It doesn't even do it's gradual power down procedure, just 'blip' straight off. Only if I disconnect the power in some way, either at the socket switch, un-plugging or removing the lead from the back, will it come on again, but it does the same thing. Now that I've read through it, I suspect it probably is the E85 PSU issue, but it's not random like people seem to be saying with that one.

Thanks also Stunty for the info.

Replacement of the regulator is certainly the first thing to try, given the symptoms.

Have another look at the power supply board and see if there is evidence of heating around the regulator.

Also checkout the larger capacitors in the same area -Are any of the tops bulging or any evidence of leakage from them. If so - replace them.

There are a couple of diodes also mentioned in that thread which should probably be replaced.