Trying to fix a PC that won't start

[E-man]

I just got this computer that wouldn't start to fix. Well first thoughts went straight to power supply. I changed it and put one in that i know works (520Watts). But when i hit the on button, nothing. I have unplugged everything except the hard drive. This is what i am trying to start with, psu, motherboard, cpu, memory, and hard drive. Well i have used one memory stick at a time and doesn't help. And tried everything i could think of,. I don't know if it is the motherboard or cpu or hard drive...


The computer is a hp pavilion a1203w
with a asus k8s-la motherboard
cpu is sempron 3000+ 1.8ghz.
40gb hard drive

Someone please help me, i will keep checking back to respond to questions. Thanks

 

[kimsland]

So you have BenchTested it?

If so, then it must be CPU or M/b
Note I have had faulty Addon Video cards do this too
Plus it's a good idea to remove all residual voltage by holding in the ON button for 30 secs, whilst power cord is out.
I did have a Case and CPU Fan cause issues too (so unplug them briefly)

That's about all

Here's the No Post tutorial: https://www.techspot.com/vb/topic53866.html

 

[E-man]

Is there a way of testing one or the other without having another pc like it? This is the only pc like this i have. Thanks

 

[kimsland]

Have you plugged both power cables into the main board?
1 x 20 (or 24) Pin Large Power Connector
1 x 4 Pin Block Power Connector (near the CPU area)

Also, exactly what are you getting, when you try turning it on?
Any Lights, Fan movement, anything at all?

 

[seanc]

Bench testing would rule out my next suggestion, but I'll throw it in anyway.

Unplug front panel USB & Firewire connectors because I've seen mangled USB connectors ground to the case and stop a PC from powering up.

 

[E-man]

I have both power cables plugged in and when i hit the button on the front nothing happens, at all. Just the click of the button.

I have unplugged everything except the hard drive. and its all the same.

Update...
I just unplugged everything including the hard drive and still nada.

 

[E-man]

I have looked for burn marks on the mobo or swollen capacitors, but i don't find anything. The only thing that gives me little concern is that hp didn't put the heatsink on the cpu very well. I took it off to check the processor and the thermal paste was on less then half the processor. the heatsink was angled a little sideways or not flush against the cpu. But the lady i got the pc from has used it for about a year and this is the first problem she has had with it.

 

[kimsland]

Have a look at ArcticSilver Instructions
Here's some of the compounds there
Also don't forget that you still need a good Heatsink

 

[E-man]

i have some artic silver.... and i fixed how it was seated on the cpu. But this isn't causing the computer to not start...it still does nothing at all.

 

[kimsland]

So you have BenchTested it?

If so, then it must be CPU or M/b
Note I have had faulty Addon Video cards do this too
Plus it's a good idea to remove all residual voltage by holding in the ON button for 30 secs, whilst power cord is out.
I did have a Case and CPU Fan cause issues too (so unplug them briefly)

That's about all

Here's the No Post tutorial: https://www.techspot.com/vb/topic53866.html

Hmm CPU or M/B is looking good (or Bad !)

 

[E-man]

Ok, thanks, i guess my best bet is to get a mobo first and see if that is it, before the cpu? Which would you replace first?

 

[kimsland]

I have two (different CPU) dead computers here I'm working on
I'm in the same boat!

But I think I have some CPUs to throw in them and test (not sure if they're bad either!)

Anyway your call
How about a whole new computer?

 

[tpbarran]

I agree that it's probably the cpu or mb. First, if you have a used cpu that fits the socket, put on some Arctic Silver and see if it boots up. It if does, unless it's a very low GHz, shut it off immed. because it could burn out if you are just using a heatsink w/o a fan. I recommend the Freezer series by Arctic Cooling, or Zalmans if they fit in your case.

It it's the MB, you'll have to spring for a new one, but something could be wrong without any visible signs.

Best,

tpbarran

 

[Speedwagon]

I had the same problem on my kids computer. I started replacing old parts with new parts and still would not boot. I finally started returning parts for Motherboard and CPU and collecting parts to build a new system this weekend. I bench test the new system and everything booted up and windows loaded. But when I put it in the existing case nothing would work. What I did was take another front panel controls switches and plugged them into the motherboard and then it worked.
What this told me was that my case was bad, even though I had a brand new power supply.
I am still not giving up on the old system.
Good Luck!