Question for PC Builders

[Fishlore]

I'm trying to put together a PC made of a bunch of old parts. I've built a bunch of PCs before, but that is always with new parts or parts that I know either work or don't. I'm trying to troubleshoot an issue with a bunch of parts in which I have no idea if they work or not and I was hoping someone would be able to help.

I basically put the whole thing together. I tried to boot it up the first time and I get absolutely nothing. No sound of hard drives, no spinning CPU fan, nothing on the monitor and no led lights on the front.

I have the power supply installed and hooked up to the motherboard. I also have the power switch cable from the case plugged into the correct place on the motherboard and tried it both upside down and rightside up just in case. There is a green light that starts shining on the motherboard called the onboard LED when the power supply is plugged in. The light pulses really fast and isn't a solid green light. I don't know if this is normal or if this is telling me that the motherboard isn't getting enough power from the power supply or if there is a problem with the motherboard or CPU. The board in question is an ASUS A7A266. I've googled this, I've read the online .pdf user manual of the board and I can't find anything useful. Looking at my working ASUS A7N8X, the light is solid green and I imagine I'd want the same on this board.

If I can't even get the CPU fan to spin or bios to start the problem obviously isn't the hard drive, ram, vid card, nic card or sound card right? It has to be a problem with the power supply, motherboard or CPU right? Is the CPU needed to run bios? I didn't think it did, but I could be wrong.

So basically I was wondering if anyone had any ideas that I could try to figure out if this is a problem with the CPU, the motherboard, the power supply or maybe something else all together.

Thanks in advance.

 

[WhiteZero]

Since your not even getting a POST or fans or anything, I'd probably suggest trying a different power supply.

But first try to test the outputs on the power supply using a volt meter. If their puting out the right ammount of voltage then the PSU is probably ok and you can move on troubleshooting.

 

[Razor]

Before putting everything in the case, you should always build the bare essentials out of the case.

Take your motherboard out of the case and lay it on the foam pad it came with and on a wooden desk or something, then put a single stick of ram in, your cpu in and your graphics. Plug in the psu and try to turn it on, if it doesn't work then you know that it is either your motherboard, your cpu or your psu. Then if you have spare ones, you try them out and till you can get it to turn on.

If you've taken it all out of the case and it works fine, the problem was either a grounding issue with the motherboard touching the case or you hadn't plugged the power in correctly. Also, make sure you checked the switched on the back of your psu was in the 'on' position, the socket was in the 'on' position and also that the power button on the case worked - a broken power button was a problem i had which confused me for a little while.

 

[Crushenator 500]

moved

 

[Fishlore]

Since your not even getting a POST or fans or anything, I'd probably suggest trying a different power supply.

But first try to test the outputs on the power supply using a volt meter. If their puting out the right ammount of voltage then the PSU is probably ok and you can move on troubleshooting.

Thanks, good idea about the voltmeter. So I suppose it's within the realm of possibility that the power supply can supply enough power to light up the onboard LED, but not enough power to run the motherboard?

I'm getting the onboard LED to light, but as I said it flickers and isn't constant. I could definitely see that as a power supply issue. I sort of looked at the power supply as an all or nothing type thing, but partial power output would make sense of the flicker.

Would it be correct to assume that since the onboard LED lights at all that the motherboard itself is okay?

Hypothetically, if the cpu was fried, would I still get the POST if the power supply and motherboard were okay?

@ Razor, good suggestion regarding the grounding. I'll have to try that tonight. Unfortunately I don't have any spare parts that I can use to troubleshoot this thing. I originally thought it might be a problem with the power switch from the case so I bought a new one of those and unfortunately that doesn't seem to be the problem.

Thanks both of you for your input.