PC trouble

I am trying to diagnose a issue with my PC. I removed all the hard drives and graphics card. Just left 1 RAM module, CPU and MB. Also reset the CMOS by removing the battery from the MB and putting it after 30 minutes. Power comes on (fans, lights on) but blank screen. Should it not boot to BIOS just using integrated graphics chip on the MB/CPU?

Here is the long story,

Windows 10 blue screened and was writing core dump and I got annoyed and turned off the power. After that I started the PC and it will just go into reboot loop. It will not even go bios screen and just reboot itself after power coming on for 4 or 5 seconds.

I removed my graphics card, all the hard drives and the memory modules and started the PC again with just the CPU and MB. It did the reboot loop thing again. Then I took off the CMOS battery from the MB and after 30 minutes put it back in. This time it did not go back into the reboot loop and power stayed on. So I just added 1 RAM module and graphics card. This time it did 3 reboot loop but booted to BIOS the 4th time. I loaded the default BIOS setting (CPU was OC before) and it was fine. So added just the SSD with windows and it was happy to boot into windows.

Once in Windows, I ran memory test, stress the CPU and graphics card for 60 minutes etc and it was fine. No sign of things overheating etc. CPU, graphics card and MB all well below 50C - 60C under load.

Then after a while I restarted the PC and it won't even go to BIOS screen. However this time around it didn't do the reboot loop. So I removed the graphics card and SSD and reset the CMOS by removing the battery. However it will not boot to BIOS using the integrated graphics chip on the CPU/MB. Only thing I have now in the PC are MB, CPU and 1 RAM module but blank screen. Should it not boot to BIOS just using integrated graphics chip if all is well?

Could be a tricky one. Maybe start by putting the graphics card back. I've noticed that some motherboards behave badly when swapping around between integrated and dedicated graphics - as if they get confused about where to send the video signal, regardless of what the BIOS settings say.

Originally Posted by lostforever
Then after a while I restarted the PC and it won't even go to BIOS screen.

Did it boot Windows though? Because Windows 10 accelerate the booting section and it is kinda a pain in the ass when you want to go in there.

As for your problem of the integrated video, what value did you select in the Bios? I believe once you set it to PCI only it never bothers with the integrated video, so if you don't put in a video card you won't see anything.

I had a reboot loop after a few seconds with my new system. Turned out I forgot to plug in the CPU power connector on the mainboard. Maybe there's a loose contact somewhere?

And doesn't your PC have an internal speaker? I mean those little things that go "beep" once during startup to say that everything is OK, and give morsecode-like beeps (BIOS beep codes) when something is wrong. With beep codes it could be a lot easier pinpointing the source of the problem. I didn't have one originally.

Originally Posted by azarhal
Did it boot Windows though? Because Windows 10 accelerate the booting section and it is kinda a pain in the ass when you want to go in there.

As for your problem of the integrated video, what value did you select in the Bios? I believe once you set it to PCI only it never bothers with the integrated video, so if you don't put in a video card you won't see anything.

It never went into windows. I didn't have HD plugged in at all. The last time I was able to get into the BIOS, PCI-E is selected since graphics card was installed. Now I can't get into the BIO with or without graphics card so can't check.

I read in few places that if you don't have graphics card in and reset the CMOS it should pick one it finds, in other words pick the integrated video but not sure how true this is.

Originally Posted by Arhu
I had a reboot loop after a few seconds with my new system. Turned out I forgot to plug in the CPU power connector on the mainboard. Maybe there's a loose contact somewhere?

And doesn't your PC have an internal speaker? I mean those little things that go "beep" once during startup to say that everything is OK, and give morsecode-like beeps (BIOS beep codes) when something is wrong. With beep codes it could be a lot easier pinpointing the source of the problem. I didn't have one originally.

I have checked the CPU connector and its fine. I no longer have reboot issues now but initially it started out that way. I don't hear any beep sound since my cases does not have speaker. Are they easy to buy? I connected head phones to the back and front of the MB sound connectors but I don't hear anything.

Originally Posted by lostforever
I don't hear any beep sound since my cases does not have speaker. Are they easy to buy? I connected head phones to the back and front of the MB sound connectors but I don't hear anything.

Beep codes are only sent to the internal case speaker AFAIK. You can search for "internal speaker" on Amazon or elsewhere.
I got this package: InLine - Motherboard Test Kit, as it includes a few more useful (if you build your own PCs) connectors, and they weren't any more expensive than single speakers. The black one on the left is the speaker. Check your mainboard manual for which pins to plug the connector in.

Originally Posted by lostforever
It will not even go bios screen and just reboot itself after power coming on for 4 or 5 seconds.?

If that PC has no SSD:
- get some friend who's into hardware stuff or go for pro service as it seems to me that something actually farted in that machine and has to be replaced.

If it has SSD:
- plug out only SSD, nothing else then post what happens when you turn it on without SSD.

There were cases where windows 10 installation goes into boot loop - the cause was an old motherboard that's not "win10 ready".
But you'd have seen a vague warning for a few days of work with win10 (SYSTEM_SERVICE_EXCEPTION) and that loop doesn't prevent user to enter BIOS or to reinstall win7/8.

I would try resetting the BIOS using the reset jumper on the motherboard. If you use the battery method, be sure to unplug the PC and the battery for several minutes to ensure all power is deprived to the motherboard.

Originally Posted by Ripper
I would try resetting the BIOS using the reset jumper on the motherboard. If you use the battery method, be sure to unplug the PC and the battery for several minutes to ensure all power is deprived to the motherboard.

If I don't have jumper caps in handy, how do I reset using the jumper? touch the two pins with screwdriver?

Originally Posted by Arhu
Beep codes are only sent to the internal case speaker AFAIK. You can search for "internal speaker" on Amazon or elsewhere.
I got this package: InLine - Motherboard Test Kit, as it includes a few more useful (if you build your own PCs) connectors, and they weren't any more expensive than single speakers. The black one on the left is the speaker. Check your mainboard manual for which pins to plug the connector in.

Thanks for the link. I will give that go. However if the MB is faulty, are those error codes any good?

Originally Posted by joxer
If that PC has no SSD:
- get some friend who's into hardware stuff or go for pro service as it seems to me that something actually farted in that machine and has to be replaced.

If it has SSD:
- plug out only SSD, nothing else then post what happens when you turn it on without SSD.

There were cases where windows 10 installation goes into boot loop - the cause was an old motherboard that's not "win10 ready".
But you'd have seen a vague warning for a few days of work with win10 (SYSTEM_SERVICE_EXCEPTION) and that loop doesn't prevent user to enter BIOS or to reinstall win7/8.

If the issue is wdue to the SSD with Win 10 on it, it should boot to BIOS with no SSD on it. However I am not even booting to BIOS now with just RAM, CPU and graphics card.

Originally Posted by lostforever
If I don't have jumper caps in handy, how do I reset using the jumper? touch the two pins with screwdriver?

Find or download the motherboard manual. It should show you where the reset jumper is. It should have a cap already on it, in the neutral position. Shift it over to the reset position, switch on, switch off, replace the cap in the neutral position, and reboot.

Originally Posted by Ripper
Find or download the motherboard manual. It should show you where the reset jumper is. It should have a cap already on it, in the neutral position. Shift it over to the reset position, switch on, switch off, replace the cap in the neutral position, and reboot.

I found the jumper where it says CMOS reset and it does not have cap on it right now. I will dig around more. thx

Thanks all for your help. It turns out the MB went bust. I bought cheap £30 MB to test my theory and all is working well so far.

Glad you found the culprit - this sort of nonsense can be hard to pin down sometimes, and be a major pain.

Thats pretty rare for a MB to die like that. I've only had it happen once in all my years in IT that it died without any burn marks or swollen capacitors. Hard as hell to diagnose as you found out. For mine, I had an extra same MB laying around so found out the same way you did after testing everything else.

Originally Posted by Toff
Thats pretty rare for a MB to die like that. I've only had it happen once in all my years in IT that it died without any burn marks or swollen capacitors. Hard as hell to diagnose as you found out. For mine, I had an extra same MB laying around so found out the same way you did after testing everything else.

I double and triple checked the old MB and I don't see any burn marks etc so its very odd. Sometime it can boot the BIOS and but not other times so its an odd issue. I hope its the MB which was really at fault and not some other parts and the old problem is hidden with the new MB! The new MB is been up and running for couple days but I haven't really used to the system in anger yet so fingers crossed still