Pc turns off at boot 1

[LilBob]

My friend has a Dell Vostro 200 that used to turn itself on during the night after it was shut down. Now it won't boot. Three to five seconds into boot, it turns off. I pulled the CMOS battery, cleared the settings & put the battery back in. Still won't boot. Replaced the PSU with a stronger one. Turned PC on, started to boot & then shut down again. Tried starting it again but nothing, no boot not even fans running. Let it sit for a while, plugged it back in & it started up on its own. Gave me the single BIOS beep & shut down again. Visual inspection of MOBO didn't show anything. Any ideas out there?

Thanks for any help you can offer, Bob

 

[mscallisto]

One single BIOS beep could mean RAM (memory)issue.

Was new RAM recently installed?
Can you remove some or all installed RAM and test?

Sam

 

[vacunita]

Remove everything, including hard drives and optical drives.

Just leave memory and CPU.

Does it POST then?

If it still won't POST with just memory and CPU, then I'd consider a motherboard problem.

Cold be a short that was causing the PC to turn on. And now its bad enough to prevent bootup.

----------------------------------
Phil AKA Vacunita
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Ignorance is not necessarily Bliss, case in point:
Unknown has caused an Unknown Error on Unknown and must be shutdown to prevent damage to Unknown.

Web & Tech

 

[goombawaho]

Before you dump the motherboard, do what Vacunita says, but do it with the motherboard REMOVED from the PC and sitting on a piece of wood or other non-conductive surface.

That will remove all other items (like front panel USB ports and shorting out against the case) as possible causes and leave just the processor, mobo and memory as the players.

I saw a PC that would not boot until one of the front panel usb headers was unplugged from the board. I never order a new board or throw one out now until testing it with the ABSOLUTE bare minimum.

 

[rclarke250]

Actually on some systems the single bios beep, is the post successfully passed message, not an error beep. I agree with Phil, and Goombawaho, sounds like it may be something else keeping a power rail down, or even a bad front panel card.

 

[LilBob]

No new RAM added. Will try all your suggestions but starting to lean more to a MOBO problem as this has been an ongoing & worsening problem for months according to him (plus his sister did something months back to the system that temporarily resolved the situation but has no idea what). I can't even get it to stay running long enough to do a repair or clean install or even to boot in safe mode. I'll try your suggestions & let all now how it worked.

Thanks for your ideas, Bob

 

[BadBigBen]

while powering up, most mainboards check the status of the HeatSink-Fan, if it is not running (or the machine thinks it is not running) then the mainboard will shut down to avoid damage to the CPU...

if you have another fan (CPU) laying around, there is a simple test, unplug the CPU FAN, then plug in the other fan (leave the HeatSink on the CPU). Apply power and see if it continues to POST... (DO NOT let it run for too long without the full cooling or place the other fan in such a manner that it blows on the heatsink)...

if it does, then you know that the CPU fan is the culprit and should be replaced...

if it does not, then proceed with what was suggested above...



Ben
"If it works don't fix it! If it doesn't use a sledgehammer..."
How to ask a question, when posting them to a professional forum.
Only ask questions with yes/no answers if you want "yes" or "no"

 

[goombawaho]

I agree that ONE beep is often the OK signal. Confirm that you CAN'T get into the BIOS when starting it up.

If you can't, then for sure there is a problem, but not saying where.

 

[LilBob]

Unplugged all drives including front panel USB ports. Got single beep & shut down a few seconds later. I'm still unable to get into BIOS when starting up. I'll try the fan idea & a few other checks to see if we can resolve this issue.

Thanks again, Bob

 

[rclarke250]

When I mentioned the front panel card, I meant the power and reset switches. unplug them and use a small screwdriver to momentarily short the 2 pins for the power switch, small percentile fix, but worth a look. Ben's idea about the cpu fan is also worth looking into, a few weeks ago I had a machine that the fan stopped spinning on, but the machine would boot sometimes. The weird thing was clearing cmos, and reseting to defaults, fixed the non spinning cpu fan. Also unplug all devices except the video, including mouse and keyboard to rule a short in a device or cable out.

 

[LilBob]

Problem resolved. I pulled a RAM stick & tried rebooting, no change. Pulled the other stick & pc powered up. Replaced drives one @ a time & finally all USB ports, PC still booted up. Replaced the defective RAM stick & reset BIOS. After a day of testing, no problems with PC turning on or off unless told to. Returned PC to friend & awaiting to hear if he runs into any problems. Thanks for all your ideas (rclarke, I should have mentioned, I also disconnected the power & reset switches). I'll let all now if he still has a problem.

Thanks for all your help, Bob

 

[rclarke250]

Sounds like you might have found it, nice job.

 

[BadBigBen]

Glad to hear that it's resolved...

Ben
"If it works don't fix it! If it doesn't use a sledgehammer..."
How to ask a question, when posting them to a professional forum.
Only ask questions with yes/no answers if you want "yes" or "no"