I thought I’d share a recent experience  – repairing our Home Theatre PC…

A couple of weeks ago – we were woken at 3am to the sound of a UPS alarm in the house.  After a blurry inspection – it appeared to be an overload alarm on the HTPC.   Unplugged everything and went back to bed!

The next day I started investigating.  As soon as I switched the PC on – the UPS tripped (and also blew the fuse to the UPS).   Not a good sign – so I started narrowing down the problem.   Eventually I found that with everything unplugged from the PSU – the UPS would still trip – so evidently the PSU was dead.  Very dead…

The next question was – had it taken anything else out with it?  So on, with the testing, tried a known good PSU – still didn’t work – lights were on but nobody home.   So either the motherboard or CPU.   I took the CPU (Core 2 Duo) out and tried in another system – it worked! So it must be the motherboard that was fried.

So – new PSU ordered (new Zalman 500W RS) – new motherboard ordered – Gigabyte EP45-DS3P – along with two new sticks of DDR2 RAM (as my existing RAM was too slow).    A few days later and everything arrives (from separate suppliers) – excellent – soon be up and running! 

No….  🙁

Plug it all in – lights come on – lights go out…    Getting frustrating now!

So – back to diagnostics – start switching things out.   Tried the known good PSU – and it boots!!  Success – but unlucky with the brand new faulty PSU.  OK  – send that back for a replacement.

Next step install the OS.  Nice and easy – have installed Windows more times than I’ve had hot dinners!    OS installed – time for the drivers.   Crash – blue screen – reboot.

OK – this is Windows 7 so maybe there’s a driver incompatibility?   I’ll reinstall again and try different drivers.   But this time it doesn’t install?   Every time I attempt an install it says that the install media is missing a file?  

Eh?  I just used this DVD 10 min ago without problems?!?!

OK – admit defeat – create a new DVD – hey presto it works.  Can’t explain it, but it works.

But then – blue screen – reboot.   Maybe Windows?  Strange though as from experience Windows 7 is the most stable Windows OS I’ve used in a long time?

Reboot again – and again – and then  I can’t even get into the BIOS !!

So – back to pulling things out.   Turns out one of the (brand new) memory sticks is faulty.  Take it out – the PC boots.   Put it in – can’t even see the BIOS screen.

Sheesh – ok – need to send back the PSU and one of the sticks.   But at least the PC is booting!    So time to install all the apps and get the data copied back over.

But still – random reboots – only maybe once a day – but still not the stable HTPC I’m used to?   Ran some memory diags and what do you know – the other memory is showing errors!   Can’t believe my luck at this point – dead PSU and motherboard – faulty replacement PSU and two faulty replacement memory sticks.

I’m not going to be beaten by this one!!

Replace with some known good (albeit slower) memory – and the tests pass 100%.  Finally – we get to watch movies, recorded TV – and no reboots!

Come down in the morning and the PC is dead – clicking on off on off on off…    This time it turns out to be a known fault with certain PSUs and the Gigabyte motherboard entering S3 suspend state.   Remove the battery – leave for a while and it booted fine.   Phew!   So disable the S3 state as I don’t want this machine to suspend anyway! 

The new PSU arrives and with trepidation – I disconnect everything and plumb it in….

Drum roll…..

It WORKS!  And – strangely enough – I’m seeing diag LEDs on the motherboard I’ve not seen before?    So maybe the RAM wasn’t faulty?   Nope – try it out and still dead.

So..

1 Dead PSU, 1 Dead Motherboard, 1 Faulty Replacement PSU, 1 faulty Windows 7 DVD, 2 faulty sticks of RAM

later..

1 working HTPC!

🙂 Glad it’s not always this difficult!