PC won't power on

[Haole Boy]

Aloha everyone. My apologies if this is a "simple" question, but I'm not much of a hardware guru. A customer brought me a machine saying it won't power on. He's about 16 and has obviously been poking around inside (CPU cooling fan not attached to the CPU - I think he said he removed the CPU to see if there were bent pins). Here's what I've tried:

• Physical inspection and it looks like everything is connected.
• I push the power button and nothing happens.
• Jumper the power switch pins on the motherboard - nothing happens
• Tried a different power supply, nothing happens
• Jumper pins 16 and 17 on the 24 pin power supply connector, I get lights, fans, etc.

So, everything I've found via google so far just says I have a hardware problem. No hints on how to pursue. Can someone please provide what to look at / for next.

Mahalo! Harry Z

 

[britechguy]

If he removed the CPU and did not apply thermal paste when firing up the system again, that could be fried.

I suspect a failed motherboard, but it could be something else.

Not that you can turn back time and refuse the job now, but if an end user tells me they've removed the CPU or done extensive messing around inside the guts of the machine, well, "I'm sorry but I will not take on this job."

 

[Markverhyden]

"I think he said he removed the CPU to see if there were bent pins)." Pins just don't get bent. So most likely it was dead to begin with and he'd been fiddling around.

You can get the make and model of the mother board. It'll be silk screened on the top some around the processor location. Grab the SM.

Pull the 2032 battery and leave out over night with the AC not plugged in. Only have the processor in, RAM and everything else disconnected. Then plug in the AC. Usually there's a LED or 2 which might provide some kind of diag code. Try shorting the power switch on the header.

 

[GTP]

I suspect a failed motherboard, but it could be something else.

"I think he said he removed the CPU to see if there were bent pins)." Pins just don't get bent. So most likely it was dead to begin with and he'd been fiddling around.

Pull the 2032 battery and leave out over night with the AC not plugged in. Only have the processor in, RAM and everything else disconnected. Then plug in the AC. Usually there's a LED or 2 which might provide some kind of diag code. Try shorting the power switch on the header.

Personally I would do exactly these steps outlined by @Markverhyden.

If you have no luck afterwards then I have to agree with @britechguy

 

[Haole Boy]

If he removed the CPU and did not apply thermal paste when firing up the system again, that could be fried.

I suspect a failed motherboard, but it could be something else.

Not that you can turn back time and refuse the job now, but if an end user tells me they've removed the CPU or done extensive messing around inside the guts of the machine, well, "I'm sorry but I will not take on this job."

Mahalo for the reply @britechguy . He did use thermal paste, but did not reattach the CPU Cooling fan securely. But I don't think he ever got it to power up, so the CPU might be OK. Also, his grandmother is a very good customer, so I took this one on. I also set expectations that I might not be able to figure it out.

"I think he said he removed the CPU to see if there were bent pins)." Pins just don't get bent. So most likely it was dead to begin with and he'd been fiddling around.

You can get the make and model of the mother board. It'll be silk screened on the top some around the processor location. Grab the SM.

Pull the 2032 battery and leave out over night with the AC not plugged in. Only have the processor in, RAM and everything else disconnected. Then plug in the AC. Usually there's a LED or 2 which might provide some kind of diag code. Try shorting the power switch on the header.

Mahalo @Markverhyden. The make and model of the motherboard is visible. But what is the "SM" you refer to?

I can try pulling the BIOS battery. Shorting the power switch on the header did not turn the machine on. Do you expect it to work after removing the battery?

Mahalo, Harry Z

 

[Markverhyden]

But what is the "SM" you refer to?

I can try pulling the BIOS battery. Shorting the power switch on the header did not turn the machine on. Do you expect it to work after removing the battery?

Mahalo, Harry Z

SM stands for Service Manual. Modern computer BIOS may have settings which interact with the OS. Usually related to recovering from a long standby period. Sometimes that can get corrupted preventing a computer from working. It's a long shot but worth a try since it's so simple.

 

[frase]

Bent pins on CPU?

LOL

 

[britechguy]

Pins just don't get bent.

Nope. They get bent when doing stupid s*it like this user did. If the thing worked when it came from the factory or builder as far as the CPU goes, don't touch it except in the most exceptional of cases.

I've actually never pulled a processor in all my years in this business and my experience with thermal paste is entirely in laptops on the heat sink side of the equation (and that's been twice in over a decade and only because the heat sink/fan assembly had to be removed to get at something else).

 

[nlinecomputers]

If it will not power on the first thing to check is the power supply and work your way inward. Is it properly connected to the motherboard? Is the 4 or 8 pin CPU power connected? Is the power button properly connected to the jumpers and so on?

Usually on DIY systems, I assume the client is totally clueless and I rip it all out and remount everything.

 

[frase]

One can jump the mobo with CMOS, works sometimes last resort kinda kickstart heart. Asus motherboards ie asrock WIll be two pins on mobo to reset CMOS, short them to reset mobo. affter her en attemtps..oooohooowww

 

[Markverhyden]

Nope. They get bent when doing stupid s*it like this user did. If the thing worked when it came from the factory or builder as far as the CPU goes, don't touch it except in the most exceptional of cases.

I've actually never pulled a processor in all my years in this business and my experience with thermal paste is entirely in laptops on the heat sink side of the equation (and that's been twice in over a decade and only because the heat sink/fan assembly had to be removed to get at something else).

Back in the day. As in 386,486 etc the pins on the CPU's were like telephone poles compared to the little twiggies of the last decade or so. While not recommended of course, more than once I was able to use my pocket knife to straighten bent pins. They'd work just fine.

 

[britechguy]

While not recommended of course, more than once I was able to use my pocket knife to straighten bent pins. They'd work just fine.

Whatever works, truly.

 

[Haole Boy]

Mahalo to all who replied. Based on Marks's advice I was able to find the User Guide (not really much of a Service Manual). Per their procedures I learned about the troubleshooting LEDs, then I reset CMOS and tried again. Same issue, but this time I knew enough to look at the LEDs. The one for the CPU stays lit. Next step in the troubleshooting guide I found is to swap parts, and I don't have a spare CPU, RAM or video card. So, called the customer and told him I'm done.

Again, mahalo to all who replied.

Harry Z

 

[frase]

Good to see you resolved the issue Mahalo. AMD are a different species, I always work on them like a surgeon. Damn when one releases the CPU it is attached to the heatsink! It requires 100% concentration as not to damage the cpu, I use a flathead screwdriver to pop it up and out

 

[Philippe]

and I don't have a spare CPU, RAM or video card.

When troubleshooting a no-power always start with a bare/minimal system i.e. mb + cpu + fan + known good psu.
(remove the battery). Still no joy -> bad mb or cpu. Very hard to tell & risky to test (the mb can fry the cpu & vice versa).

 

[Porthos]

A customer brought me a machine saying it won't power on. He's about 16 and has obviously been poking around inside (CPU cooling fan not attached to the CPU - I think he said he removed the CPU to see if there were bent pins).

That would have been a full-stop NO for me to even consider looking at it.

 

[frase]

Yup do it yasuffer, I call them. Yea so I watched a guy on youtube, please stop..mmmm