PC won't boot

[yello]

(I thought there was a dedicated IT/tech forum so apologies if this is in the wrong place)

Help me puzzle this one assembled geeks and nerds of the CycleChat massive...

I've got an OLD Dell Vostro PC with a generic AMD motherboard that regularly doesn't boot to BIOS. It runs (when it boots up!) a version of Lubuntu - not that that's relevant since it's not even getting to the OS and drivers etc.

I suspect it's a problem with the VGA on the board but I'm not sure how I can confirm that. I've swapped monitors and VGA cable, even tried an HDMI monitor - same thing, doesn't boot up. Just loops booting, recycling power, booting until I switch it off. I get 'No signal' displayed on the monitor when powering on the PC. Both monitor and cable work fine on another PC/laptop.

I've tried reseating the SATA to disc drive cables in case it's not detecting the drives, and swapping SATA ports. No joy. Obviously, I can't get to BIOS so can't boot a USB stick.

On the occasions it does boot up, everything will run fine, sometimes for several hours, sometimes I can even successfully power it down, but often it just freezes and the monitor displays garbage - hence me suspecting VGA, or graphics more broadly.

Any thoughts people?

 

[Profpointy]

Does it do the various "beeps" when it half-boots up?

You may or may not be aware, but the beep sequence is a code which can help indicate what is amiss. I'd been in the industry for a long time, including a few years with PC based systems, before I learnt this when diagnosing a DoA new ethernet card in my home PC

 

[yello]

Does it do the various "beeps" when it half-boots up?

You may or may not be aware, but the beep sequence is a code which can help indicate what is amiss. I'd been in the industry for a long, including a few years with PC based systems, before I learnt this when diagnosing a DoA new ethernet card in my home PC

I was aware but in this case there are no beeps. I wouldn't call that definitive though since there is no sound card and I hear nothing on the generic audio jack output (headphone).

 

[yello]

Weird... completely unintentional but I booted WITHOUT the monitor attached, it seemed to have booted up so I connected the monitor et voila! everything is up and running. I wonder if it'll boot with the monitor off? More experiments to follow...

Edit: Yep, it appears to boot up ok if the monitor is off. Now to see how long to last before it freezes up, IF it freezes up.

 

[midlife]

When I was a bit involved with this years ago, whenever PCs failed POST it was either flaky RAM or Graphics card, occasionally the PSU. Most of them bleep though or had LEDs on the motherboard that lit up.

 

[yello]

No leds on the motherboard either sadly. The PC's still up and running though. I fully anticipating it to freeze up again because although it boots with the monitor off, I can't see that that'll solve the issue. It passes a memtest so praps a graphics problem??

 

[bikingdad90]

Have you got another port you can attach the monitor too that bypasses the graphics card, one on the motherboard direct?

 

[ebikeerwidnes]

If you have any empty memory slots then try swapping the memory around so that different ones are empty

sometimes help
or boot it - when you can - using one memory card less and see if it works and is more reliable - that would point to a dodgy memory card