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I have very old motherboard , CPU , power supply.
Motherboard : Gigabyte G31M-ES2C
CPU : Intel Pentium Dual Core E2160 @ 1.8GHz
Ram : Transcend 2GB ddr2 800MHz.
Power supply : Tech-Com 450Watt.
The rig worked fine for over 5years. Suddenly it stopped booting without any error code and POST screen or video. I disconnected everything and kept bare motherboard with CPU, RAM and power supply on table and powered on, again it fails to boot without any beep codes.
The CPU fan rotates and power supply unit fan rotates and power on led lights up. The CPU gets heated as well. But speaker doesn't emit any beep codes. The speaker is working because previously it used to emit short beep code during POST.
I cleared cmos and still the same results.
When I connect a PS/2 keyboard and turn on the power source, the leds (numlock, capslock, scrolllock) on the keyboard flash for a second. This used to happen even when PC is fine. So, with this can we say the motherboard is fine?
If Ram alone is faulty, I think it emits some beep codes. Might not be ram alone. To support this, I removed ram stick and turned on, still no beep codes or POST. So, might not be RAM alone.
My suspect was either the power supply or the CPU? Could it be CPU fault when no beep codes are emitted?
Finally I opened the power supply, which was long out of warranty. I found a big transistor leaked some red fluid which was gel like and hard. This might have happened long back because it wasn't fresh. So, could it be power supply's fault?
I have no doubles to check which one is faulty. Thanks
EDIT:
I have tested the smps alone connecting the green wire and black wire. When power is connected the fan rotates in smps, meaning it might be ok.
Attaching picture of leaked transistor or whatever it is..
EDIT 2:
I will be getting a new PSU anyway.
- If there are no beep codes, MB could be faulty.
And is there a bios beep code when everything is working with faulty cpu alone?
EDIT 3:
I have thrown up SMPS. And got the MB, RAM, CPU checked in a repair shop and was told that the issue is with MB alone. RAM and CPU are fine. Took the MB to service center and was told they don't service for out of warranty products even if I pay them. Then took the MB to another repair shop, that guy told he will repair it but needs like 3hours and charges around 1 / 5th the original MB price. I said OK and returned back after 3 hrs to see it was booting fine. I asked what was the problem, and he told display IC is damaged and was replaced. Don't know how much that costs but the board works now. Also purchased another SMPS and it is working fine now.
EDIT 4:
Now that I thought the MB has been fixed, I purchased an old refurbished Core 2 Duo CPU (E6750 @ 2.66GHz , 4MB Cache and considerable upgrade from Pentium dual core E2160 @ 1.8GHz 1MB cache) and replaced the CPU. I was shocked to see the same No POST, No beeps , No Display again. I thought the CPU was dead and switched to my old working CPU. To my surprise both CPU s gave the same result No POST, No Beeps, No Display. This time I'm very sure that the problem is with CPU socket. I carefully observed the CPU socket and took a piece of paper and slided through each pin rows and columns. Also couple of pins seemed bent, so I gently moved them to normal position again. And inserted the new CPU and tried again. This time it gave POST and beep successfully. Then I realized that the repair shop guy deceived me. He didn't change anything. All he did was to straighten few CPU socket pins and grab some money telling some sort of technical chip is damaged. Now I'm very sure that the old Power Supply unit is even fine, although I have thrown it away. My bad that I didn't mention that I have opened CPU initially before getting this No POST errors.
I will never open the socket again and suggest the same. Never open old MB CPU socket when there is no need. I will post an answer that helps troubleshooting.
6I'm saying this because it is important: you either have balls of steel or you don't know what you're doing. NEVER open a power supply unit, they are black boxes and if you even accidentally touch the wrong thing inside you can be instantly made deader than a doornail - even if everything is unplugged, capacitors and such. Junk that PSU, don't touch it again, and bench test with a known working one to see if the PSU took everything with it when it went. – headkase – 2016-03-11T13:26:21.287
You don't get it. I'm not connecting an opened psu to power outlet. I do know there is AC power inside and I do verify with an electric tester before even touching anything. – Bharat G – 2016-03-11T13:30:40.650
6No, you don't get it. It doesn't have to be plugged in. The capacitors hold a charge and if you accidentally short them - say with your finger - then you won't be here to argue with me about who's right. – headkase – 2016-03-11T13:31:31.900
@headkase is correct. Bin the PSU and get a new one. It is not worth the risk. – Burgi – 2016-03-11T14:09:54.617
1Thank you. I'm throwing away the PSU . It will be a while to get all of these components tested. If there is no beep codes, MB could be faulty. And is there a bios beep code when everything is working with faulty cpu alone? Anyway I'm getting a new PSU. My main concern is with MB, hope it is ok. – Bharat G – 2016-03-11T17:15:07.367