New motheboard: still no POST.

[Kalmah]

The original thread is here.

Symptoms:

*no post, no beeps, no signal to monitor, cant get to BIOS

*cpu, video card and case fans power up

*when psu is turned on, all fans run without having to push front power button

*with different psu, I have to push the front power button to turn fans on; like it should be - still doesn't POST or get signal to monitor(this is a different psu that I tried, it's not mine)

* different video card doesn't do anything

*motheboard outside of the case, stripped to cpu, memory and video card doesn't work
------------

The psu has been tested. It gives all the correct voltages.
The same thing happens with 2 different motherboards. (asus p4c800 deluxe & asus p4s800d-x)

Now to the details:
Originally the computer was:
asus p4c800 deluxe
p4 3.0ghz 478 socket
corsair twinx extreme pc3200 512x2 ram
geforce 6800 gt
coolmax 550 watt psu

It was built about 3 years ago. Never had a problem.
2 weeks ago I put the system in standby. Came back an hour later to find that it wasn't in standby anymore. The fans where all running and their was no signal to the monitor. I pushed the front power button and reset button and it didn't do anything.. fans kept running. (held them down for 10 seconds each.. and both at the same time.. tried every combination I could)

Then I flipped the psu switch off in the back. When I turned the psu switch back on the fans automatically start running without having to push the front power button. It's like the system is stuck indefinatly in an -on- state. (if psu is on, everything powers up.. psu is off, everything is off; front power button does nothing)

After 2 weeks of investigating I baught a new motherboard. The asus p4s800d-x. And I also baught a new case because I didn't like the original one..

So with the new mobo and case...
It didn't work from the start just like before. I tried with just cpu, memory, ram and psu- and with all hard drives and disk drives plugged in; both ways didn't work. After about 6 hours I turned it on and it booted up to windows!! I don't know what I did, I don't remember. So I shut it down and conected the floppy and cd drives. I turned it back on and it was dead again!!! Just fans spinning..
I disconnected the floppy and cd drives which didn't reverse what happened.. it still didn't work.

I'm stuck.

Please if anybody has any ideas I will really appreciate it.

 

[mechBgon]

1) just in case you overlooked it, did you plug in your ATX12V cable? It's the one with two yellow wires and two black wires. This is teh importants.

2) unplug all excess fans from the motherboard's 3-pin headers. If you have a 3-pin-to-4-pin adapter, use that to power your CPU fan as well. I've seen low RPM readings make some motherboards refuse to POST. Truth is stranger than fiction...

2) aside from the Geek Squad guy, have you gotten a new PSU of good quality and adequate wattage yet, and tested it with that? I saw you tested your CoolMax unit, but it still may be the root of the problem. Try an Enermax, Seasonic, Fortron, Antec, or something else that's, um, better than a CoolMax

3) hook up the case's speaker to the motherboard. There aren't any beep codes? If not, unplug the system and deprive it of the CPU, video card and RAM, then plug it in, power it up, and see if you get beep codes now.

4) the different video card that you tried... what kind was it? Is it verified working in its own right?


If I think of any other stuff to try, I'll post them too. Good luck

 

[Zepper]

As a favor to Navid,

Boilerplate-01:
. Common causes of failure to boot (no video, no beeps) assuming PSU isn't totally dead:
1- RAM, CPU and/or AGP video card not seated properly, a bent pin or corrosion.
2- Drive data cable on upside down or only on half the pins or shifted a pin or two (usually Floppy or Zip drives).
3- CMOS needs to be cleared (AC power must usually be disconnected or attempts to clear CMOS may fail) Unless your mobo does not use a power-off CMOS clear - check your mobo manual for specific info.
4- On some new mobos there is a CPU protection feature (esp. on Asus/Asrock Athlon/Socket A mobos) that will not allow the system to start if there is no fan (or a fan without a working speed sensor wire) connected to the CPU Fan power connector on the mobo (specifically marked "CPU Fan"). If you tried to start your machine without a fan properly connected, you have to attach a proper and working fan with speed sensor and clear the CMOS before it will boot.

Apparently something is wrong with the first PSU as there should be nothing but 5V standby power unless the case's Power on button is pushed. Also you should check your front panel header to make sure the LEDs are connected to the proper pins. LEDs can short things that shouldn't be shorted...

Good luck,

.bh.

 

[pkme2]

You got a short somewhere since you get no beeps. I'm trying to come from another direction.
You changed PSUs. no problem here.
You changed mobos, no problem here.
You changed video cards, no problem here.
You're still using same CPU? ????? If CPU wasn't seated right, you would get a loud beep, but nothing. Odd?????
Can you check the pins on your CPU and reset.
Try again.

 

[ElTee]

I had a similar problem with my system.

The fans would run, but the system wouldn't post, the monitor didn't get a signal and I was unable to get into BIOS. No beeps, nothing...
Since my warranty hadn't expired I returned the system to the store, having tried both a new PSU and a new video card without any success.
Once I got the system back from the store I noticed they had had to replace both the motherboard and the CPU.
I see you have tried to exchange the mobo, but have you tried to exchange the CPU? It might be that the CPU is toast...

 

[Kalmah]

Thanks all. I'm going to go down the list and check everything that was mentioned. I may be able to get my hands on a different psu today so that I can troubleshoot with one that I know works.

I'll post back. I appreciate it.

 

[Kalmah]

Sorry guys.. this was stupid of me to not check in the first place. I feel stupid now.

Bad stick of ram.

I got it to boot with nothing hooked up to it. (just cpu and 1 stick of memory).
I noticed that it detected my ram as pc1600 when in fact it's pc3200. I got into the BIOS. Set the ram frequency to 400mhz instead of auto. I'm not sure if it's still detecting it as pc1600, I forgot to look..

But then I put the second stick of ram in(instead of going full blown and hooking everything up like I did before) Turned it on and nothing happened. Took that same stick back out and it would boot. Took the first stick back out and put the potentially bad stick in the dim that the first stick was in. Didn't boot. Put the good stick in and it boots.

I'm going to hook up the original motherboard with that 1 stick and see what happens.

Does anybody know which board is better performance wise? (asus p4c800 deluxe or asus p4s800d-x) I havn't been able to find any benchmarks on the p4s800d-x. Trying to decide if I want to send the new one back. I know the new one has less bells and whistles.. but it does have this hyperstreaming that the p4c800 deluxe doesn't have. (not to be confused with hyperthreading that both have)

I appreciate everybody's help. Thanks alot.

 

[Navid]

What happened to the PSU puzzle?

With only the good stick of RAM in, does it still power up as soon as you flip the switch at the back without pushing the case power button?

 

[Kalmah]

Yeah, the psu still powers up the fans without hitting the front button. (they run slow though) then when I hit the front button everything turns on full blast.

I was thinking that it might be a feature of the case itself. (its an antec ninehunded gaming case).. maybe it's on a timer to keep the fans running for a while after it's shut off or something? link

No... that can be anyways.. it still does it even when the case power buttons are not plugged into the motherboard.

So their is something wierd with the psu. I'll have to replace it later on down the road. I'll just have to get use to shutting down, then flipping the psu off because the fans keep running.

 

[Navid]

I wouldn't use that PSU until I figured out what was going on. If something is wrong with the PSU, you could be damaging more expensive equipment. Who knows why that faulty stick of RAM is faulty!

 

[Kalmah]

Yeah, there is definatly something wrong with the psu. It's kind of strange how the system gets started.

First I turn the psu on, fans run. Then I push the power button, fans run hard suddenly.

after about 5 seconds......... the yellow light on the monitor turns green. The monitor lights up just in time to see the end of the mobo boot screen. I wonder why the delay?

I'm having some issues with the board that seem to be common for it as well. I keep getting an 'overclock failed' message on boot. But nothing is overclocked that I can tell. (I've read alot of issues with this on this board)

Why are the ram timings always listed in a different order in the BIOS than on the ram descriptions themselves? My timings should be 2326-T1. But they are listed in a different order.. so I'll have to look into that before I can change it off auto.

I got stuck with babysitting my neice.. so I'm unable to do anything right now. I want to hook the old motherboard up and see if it still works. And then decide if I want to keep this new board or not.

I'll also be able to test a different psu later.

 

[mechBgon]

Throw that PSU away before you fry something.