****** PC Won't Power Up!!

[Chrishazle]

A little while ago the PSU on my PC packed up so I replaced it - went750W rather than the 500W that was original. Carefully re-plugged everything in the correct place, all initially OK but then on boot-up it said "CPU Fan Fault, press F1 to continue" so I pressed F1 and all worked well. Then we got hotter weather and things were not so good, PC occasionally going black screen and switching off. It's a bit of a PITA unplugging the box and moving it, monitor, keyboard and mouse to dining room so as after a cool down the PC would work again, but yesterday it decided to not power up at all, so this morning I've moved it to the "comuter workshop" (dining room).

First thing I checked was that in my study I had power to the PC - avo into the plug that goes into the back of the box showed 249V. Then I set up power supply to the monitor and box in the dining room, again 249V at the plug into the back of the box. Opened the side of the box and could straight away see that there were spare leads interfering with the operation of my main coolermax CPU cooler so tie wrapped them out of the way (new PSU has far more output leads and connectors than old one). Flipped the power on, the second case fan I installed some years ago started to turn then stopped, coolermax fan and PSU fan did not kick in, no power light on front of box. Noticed second case fan was very dusty so took it out and blew all the dust off (compressor, workshop) so fan spun easily, so re-installed it, turned power on, no change, no coolermaster fan, no PSU fan, second case fan started to spin but within a second stopped, no power light on front of box.

Only way I could figure to see if the PSU was seeing power was to bull one of the white (Molex?) 4 pin connectors apart and stick my multimter probes into it, got 5V DC across 2 pins (red and yellow) so lookss like power is getting to and from the PSU.

So - what could be stopping power getting to the appropriate place to instigate boot-up? Could it be the little coin cell (2042 IIRC same as our MB keys!). Could it be that I have cooked the CPU? Not sure what to try next, other than attempt to source a new ATX tower case with 2 x 5 1/4 front bays for DVD drives, at least 4 spare 5 1/4 bays for HDD's/SSD, front USB's and SD card reader, maybe new mobo with 6 SATA, IDE slots etc, plus suitable CPU and RAM - awkward and expensive method I think, but as I have 16GB DDR2 RAM, good video card, new 850W PSU, quite new coolermax CPU cooler, 3 IDE cards for extra USB's and firewire (for videocam), 2 DVD writers - and a load of essential stuff on the existing HDD's - I need to get back up and runnung - or get some external HDD USB cases as wife's PC (which I'm now on) has no spare internal bays at all.

Thanks for taking the time to read this, and TIA for help.

 

[SpikyMikey]

A little while ago the PSU on my PC packed up so I replaced it - went750W rather than the 500W that was original. Carefully re-plugged everything in the correct place, all initially OK but then on boot-up it said "CPU Fan Fault, press F1 to continue" so I pressed F1 and all worked well. Then we got hotter weather and things were not so good, PC occasionally going black screen and switching off. It's a bit of a PITA unplugging the box and moving it, monitor, keyboard and mouse to dining room so as after a cool down the PC would work again, but yesterday it decided to not power up at all, so this morning I've moved it to the "comuter workshop" (dining room).

First thing I checked was that in my study I had power to the PC - avo into the plug that goes into the back of the box showed 249V. Then I set up power supply to the monitor and box in the dining room, again 249V at the plug into the back of the box. Opened the side of the box and could straight away see that there were spare leads interfering with the operation of my main coolermax CPU cooler so tie wrapped them out of the way (new PSU has far more output leads and connectors than old one). Flipped the power on, the second case fan I installed some years ago started to turn then stopped, coolermax fan and PSU fan did not kick in, no power light on front of box. Noticed second case fan was very dusty so took it out and blew all the dust off (compressor, workshop) so fan spun easily, so re-installed it, turned power on, no change, no coolermaster fan, no PSU fan, second case fan started to spin but within a second stopped, no power light on front of box.

Only way I could figure to see if the PSU was seeing power was to bull one of the white (Molex?) 4 pin connectors apart and stick my multimter probes into it, got 5V DC across 2 pins (red and yellow) so lookss like power is getting to and from the PSU.

So - what could be stopping power getting to the appropriate place to instigate boot-up? Could it be the little coin cell (2042 IIRC same as our MB keys!). Could it be that I have cooked the CPU? Not sure what to try next, other than attempt to source a new ATX tower case with 2 x 5 1/4 front bays for DVD drives, at least 4 spare 5 1/4 bays for HDD's/SSD, front USB's and SD card reader, maybe new mobo with 6 SATA, IDE slots etc, plus suitable CPU and RAM - awkward and expensive method I think, but as I have 16GB DDR2 RAM, good video card, new 850W PSU, quite new coolermax CPU cooler, 3 IDE cards for extra USB's and firewire (for videocam), 2 DVD writers - and a load of essential stuff on the existing HDD's - I need to get back up and runnung - or get some external HDD USB cases as wife's PC (which I'm now on) has no spare internal bays at all.

Thanks for taking the time to read this, and TIA for help.

You say you're getting 5V out of it, but are you also getting 12V?

 

[Chrishazle]

I didn't think to check the other 2 connectors in the molex, assumed that as I had 5V the PSU was OK - plus it's less than 2 months old! Will check.

On the Molex it's red, black, black, yellow, checked 2 of them, first gave 4.5V red to yellow, nothing on either black to yellow but that is a spare male. Second one gave 4.5V from reb to yellow and same from either black to yellow.

Where can I check for 12V?

 

[markmifsud]

One thing that could be an issue is a fried CPU, when you changed the PSU you said that you had a CPU fan error and F1'nd though that. Has this been running sinse that time with no active cooling on the CPU. Also, do you get any been codes at power up, depending on the board there are a set of beeps that indicate where the fault may be.

 

[Chrishazle]

ATM I'm getting absolutely nothing from the PC, the monitor says "cable not connected" although it is, no power light on the front, no beeps and whirrs, nothing. The CPU has a very large coolermax CPU cooler properly attached to the top of it, with its own fan which may not have been working although I could hear a fan running when the PC previously booted up, even when it very swiftly went black screen switched off. I guess there's a fan in the PSU as well as the coolermax and the second case fan.

 

[SpikyMikey]

I didn't think to check the other 2 connectors in the molex, assumed that as I had 5V the PSU was OK - plus it's less than 2 months old! Will check.

On the Molex it's red, black, black, yellow, checked 2 of them, first gave 4.5V red to yellow, nothing on either black to yellow but that is a spare male. Second one gave 4.5V from reb to yellow and same from either black to yellow.

Where can I check for 12V?

Is this an ATX?

 

[Chrishazle]

Yes, it's a full fat ATX with not just 2 front 5 1/4 bays for my DVD drives but also 4-5 5 1/4 drive bays where I have the primary SSD in a caddy and 2 or 3 HDD's, plus there's a 3 1/2 front drive bay with a couple of USB's and a multi-disc SD card reader, also on the mobo I have 6 Sata's, 5 expansion slots with 4 populated, and oh yes a top pop-out with 2 USB's and an audio connection. Mobo is an Asus A3A79-T Delux. Running Win10 upgraded from Win7 and not suitable for Win11.

 

[SpikyMikey]

Yes, it's a full fat ATX with not just 2 front 5 1/4 bays for my DVD drives but also 4-5 5 1/4 drive bays where I have the primary SSD in a caddy and 2 or 3 HDD's, plus there's a 3 1/2 front drive bay with a couple of USB's and a multi-disc SD card reader, also on the mobo I have 6 Sata's, 5 expansion slots with 4 populated, and oh yes a top pop-out with 2 USB's and an audio connection. Mobo is an Asus A3A79-T Delux. Running Win10 upgraded from Win7 and not suitable for Win11.

You need to test on the big 24 way 2 row connector. Pinouts are here:

If you unplug the mains and disconnect the 24 way plug and jump pins 16(power on) to ground (15 or 17 being the nearest), when you plug the mains back in the psu should come alive and the its fan should run. If not, it's a dud - although you could double check with your multimeter for the various output voltages as listed above, eg +12v on pins 10 and 11.

 

[Chrishazle]

thanks @SpikyMikey, you're taking me way byond my pay grade especially as I have a couple of other things going on ATM - like wife recovering from fusion op on her right thumb (which includes a screw put in from the top of the thumb to below the first joint!! Not easy getting a self tapper to cut a thread into bone, as she discovered!) and me having 3 skin strips needing local surgery intervention late this afternoon (cue massive pain as existing daughter installed dressing was removed!) . Why do problems never come in ones, only 3's!!

I spent some time this afternoon looking at available PC cases without seeing anything like the ATX case I have, I've also had comment above from Markmifsud that I may indeed have fried the CPU - but although I can remember that the CPU is an AMD Phenom 4 core, I can't remember exactly which one it is, and as I also can't find the box from the Cooler Master CPU cooler I can't find the spare cleaner and glue, let alone the instructions for installing or removing it. The only saving grace is that I still have some internet access via wife's PC!

Maybe I should do what happened a year or so back - a good friend got fed up with problems on his PC and bought new, we then dismantled it and listed useable bits on ebay, recovered a decent percentage of the cost of the new PC that way. Trouble is I want to retain the HDD's/SDD, DVD drives, video card, USB and firewire cards, cooler master CPU cooler - so if the CPU is toast there's only the Mobo and 4 x 4Gb DDR2 RAM strips, so not worth a lot, and a new PC would cost IF I can find one with enough nays and IDE slots!!

 

[SpikyMikey]

thanks @SpikyMikey, you're taking me way byond my pay grade especially as I have a couple of other things going on ATM - like wife recovering from fusion op on her right thumb (which includes a screw put in from the top of the thumb to below the first joint!! Not easy getting a self tapper to cut a thread into bone, as she discovered!) and me having 3 skin strips needing local surgery intervention late this afternoon (cue massive pain as existing daughter installed dressing was removed!) . Why do problems never come in ones, only 3's!! I spent some time this afternoon looking at available PC cases without seeing anything like the ATX case I have, I've also had comment above from Markmifsud that I may indeed have fried the CPU - but although I can remember that the CPU is an AMD Phenom 4 core, I can't remember exactly which one it is, and as I also can't find the box from the Cooler Master CPU cooler I can't find the spare cleaner and glue, let alone the instructions for installing or removing it. The only saving grace is that I still have some internet access via wife's PC! Maybe I should do what happened a year or so back - a good friend got fed up with problems on his PC and bought new, we then dismantled it and listed useable bits on ebay, recovered a decent percentage of the cost of the new PC that way. Trouble is I want to retain the HDD's/SDD, DVD drives, video card, USB and firewire cards, cooler master CPU cooler - so if the CPU is toast there's only the Mobo and 4 x 4Gb DDR2 RAM strips, so not worth a lot, and a new PC would cost IF I can find one with enough nays and IDE slots!!



Sounds like you have more than enough on your plate right now and I would never encourage messing about with sparks (even 12v ones) if you're not comfortable with it. If you're not stranded for computer access, it might be best to push it all to one side for a while. If at some point you feel like stripping out the psu I'd be more than happy to bench test it here; I'm only 'across the border' in East Sussex.

 

[Chrishazle]

Thanks @SpikyMikey, much appreciated too, late at night especially as I needed a stiff drink after nurse removing the dressing from my left elbow earlier. We lived in East Sussex for 24 1/2 years in Crowhurst near Battle, bought the house in 1982 with the intention of being buried from there but Gordon Brown screwed that plan so we downsized to Woodchurch near Ashford and put a healthy 6 figures into our retirement fund - but it looks like Reeves is going to further screw our retirment planning! Tempted to spend the lot then take our begging bowl to the DWP and let them finance out retirement! Somehow suspect that DWP contribution would be nowhere near what we take from our retirement savings each month, so quality of life would degrade.

Possible main problem is that although I have some saved logins on wife's PC a lot are on mine (unless I can rescue them from my tablet which is sync'd to my PC), as are things like our main address book on Access, so maybe one approach is to set me up on a seperate account on wife's PC and get HDD USB caddies for the HDD's on my PC as I have most saves set up not on the primary C drive but on the E HDD - but it's too late and too many glasses to think straight.

Really appreciate your help.

 

[Smart320]

Sounds painful both personal and computer wise , hope recovery is swift on all fronts

 

[SpikyMikey]

Thanks @SpikyMikey, much appreciated too, late at night especially as I needed a stiff drink after nurse removing the dressing from my left elbow earlier. We lived in East Sussex for 24 1/2 years in Crowhurst near Battle, bought the house in 1982 with the intention of being buried from there but Gordon Brown screwed that plan so we downsized to Woodchurch near Ashford and put a healthy 6 figures into our retirement fund - but it looks like Reeves is going to further screw our retirment planning! Tempted to spend the lot then take our begging bowl to the DWP and let them finance out retirement! Somehow suspect that DWP contribution would be nowhere near what we take from our retirement savings each month, so quality of life would degrade.

Possible main problem is that although I have some saved logins on wife's PC a lot are on mine (unless I can rescue them from my tablet which is sync'd to my PC), as are things like our main address book on Access, so maybe one approach is to set me up on a seperate account on wife's PC and get HDD USB caddies for the HDD's on my PC as I have most saves set up not on the primary C drive but on the E HDD - but it's too late and too many glasses to think straight.

Really appreciate your help.

Any time Chris - you can always PM me on here.
I'm in no way a computer expert; they're a necessary evil as far as I'm concerned, but I handle PSUs almost everyday, integrating them into the systems we build, and one SMPS is pretty much like another!

 

[grober]

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[Doodle]

Trouble is I want to retain the HDD's/SDD, DVD drives, video card, USB and firewire cards, cooler master CPU cooler - so if the CPU is toast there's only the Mobo and 4 x 4Gb DDR2 RAM strips, so not worth a lot, and a new PC would cost IF I can find one with enough nays and IDE slots!!

I'm with Mark on this one, the F1 CPU fan fault was a warning sign and one that needed attention at the time. The black screens and shutdowns you mention are most likely the overheat protection forcing a shutdown to try and save things, but the ultimate conclusion is usually a cooked CPU which would explain its failure to POST fully (Power On Self Test - lights and/or beeps when you start up).

Sorry to be the bearer of bad news, but I fear you're on a hiding to nothing in terms of substituting hardware. Finding a case with enough slots to mount the DVD drives is doable - they are still out there and anyway, it's quite possible you can repurpose your existing tinware - but DDR2 and IDE are dead in the water. I think it's been well over 10 years since I last saw a new stock motherboard with any sort of IDE on it, and DDR3 has been around for nearly 20.

I've had good success with a USB adapter to hook up IDE drives to modern machinery - I recently skipped an old server that had been in the loft for nearly 20 years, and used one of these to copy off the data for review before destroying the drives. Sadly the transfer speed is still limited by the IDE side of things though

 

[Chrishazle]

Thanks @Doodle, but things have progressed via PM with @SpikyMikey, I now know that the PSU is fine, have ordered a replacement Phenom II X4 125W which I think is identical to what I installed in 2012 (and had to change the mobo as a result as the original could not handle a 125W CPU), found the box for the coolermaster CPU cooler so have that off ready for the arrival and installation of the replacement CPU, and just to add to the fun, having removed the CPU cooling fan and coolermaster air cooling bit, decided to power on - and lo and behold the machine powered up, booted - as expected to "press F2 to enter CMOS and correct date etc", got into CMOS, changed time and started changing date when click, black screen and machine powered off. Confident now that CPU is toast, replacement will sort problem, and hopefully before weekend all will be back to rights.

 

[Doodle]

Fingers crossed!

 

[Chrishazle]

Replacement CPU arrived this morning, all installed, initially it was not seeing my primary SSD, turned out the power supply for it was not connected, soon fixed. All back up and running, but possible my saved logins have gone missing as I had to enter username and password to get into here, hopefully sync with my tablet will cure that. Anyway, all now looking good, CPU and case fans both running well. Phew!!

 

[Spudgunandy]

I haven't a clue what you lot are talking about. But I can field strip a luger

 

[SpikyMikey]

Replacement CPU arrived this morning, all installed, initially it was not seeing my primary SSD, turned out the power supply for it was not connected, soon fixed. All back up and running, but possible my saved logins have gone missing as I had to enter username and password to get into here, hopefully sync with my tablet will cure that. Anyway, all now looking good, CPU and case fans both running well. Phew!!

For a moment there I thought you were going to say it had all gone TU
Glad you got it sorted.