Failed POST, auto reboot

Killerkebab

Killerkebab

Killerkebab

Soldato
Joined
27 Mar 2004
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Kent
First off I'd like to apologise for the long post, but I figure any information could help. The actual problem I have is in the last couple paragraphs :p

I've recently hit a major dilemma with my PC. Recently for no apparent reason, hardware has been failing. I bought the parts for the PC in 2006 and it has been fine since then, until around January this year.

Without warning, my two raptors (in RAID) stopped working whilst the computer was running. The RAID array was obviously lost and I had to RMA.
Fast forward a few months, the new drives are here courtesy of WD, have been fine (for now) and suddenly the same thing happens. The PC freezes (I wasn't using it at the time, it was idle this time), I turn it off and on only to have the onboard RAID tell me the array has failed. I have sent off an RMA again.

In the meantime I bought a cheap internal 500GB drive to tide me over. However after a few weeks of use, windows 7 said something might be wrong with the drive - I downloaded SeaTools which informed me the drive has failed a SMART test.

Fast forward a couple weeks. The PC then started emitting beeps whenever I boot. I check BIOS... apparently the CPU fan speed is 0rpm! I decided to turn the machine off.
All these drives failing and the CPU fan going down led me to believe the motherboard is at fault (probably a stupid idea in hindsight, but I figured the SATA controller was bad and the board was slowly screwing everything else up) so I got it replaced when I got some money together.

I boot my new system up, and... beeeeeeeeeeeeep. I open the case up, the CPU fan isn't spinning. I then decided to get a new CPU fan. Cleaned the processor, attached the new fan, started the computer up and... beeeeeeeeeeep. Same reason.

I then did another possibly stupid thing, since I bought the motherboard from the MM, I decided to clear the CMOS. Now when I turn the computer on, nothing happens. The PC seems to start up, I hear a couple fans spinning, and after maybe a couple seconds, the PC reboots and does this all over again.

Specs here:
E6600
4GB of PC2-6400
ATI HD4700

First motherboard: Abit AB9-Pro
Replacement: Gigabyte P43-ES3G

2x 150GB raptors (though not plugged in any more because I fear for them :p)
1 500GB Seagate

PSU is Antec NeoHE 500W
 
Ok first off don't say beeps or beeeeeep. This is POST the number of beeps actually helps you diagnose what's going on.

Try another PSU if you can borrow one that would help. How did you clear the cmos did you just remove the battery or did you do it by moving the jumper? Check the jumper was put back maybe?

It is possible you are just unlucky with the mobo's or something went wrong when u fitted it. I have had people bring me "problem" pcs and found they had put a screw in a hole without the standoff and it was shorting out on the board.

Remove and replace the mobo, check the standoffs line up to the holes. Ensure you put the PSU connectors in correctly (some people forget the 4pin or 8pin plug!) and try the system with just 1 stick of ram (swap to check them).

Keep us posted on what you try and what is happening
 
From your new motherboard's manual..
Your Motherboard's manual said:
Q: What do the beeps emitted during the POST mean?
A: The following Award BIOS beep code descriptions may help you identify possible computer problems.
(For reference only.)
1 short: System boots successfully
2 short: CMOS setting error
1 long, 1 short: Memory or motherboard error
1 long, 2 short: Monitor or graphics card error
1 long, 3 short: Keyboard error
1 long, 9 short: BIOS ROM error
Continuous long beeps: Graphics card not inserted properly
Continuous short beeps: Power error
Click to expand...

Does that help you?

Source Gigabyte
 
Sorry, on the Abit board the beeps I was getting were warning beeps for CPU fanspeed being under, and if the PC was running for long enough, I'd then get beeps for CPU temp above 65 degrees. I only know this because I disabled the temp/fan warnings in BIOS and suddenly heard nothing :)

On the Gigabyte board I got a constant beep which didn't stop until I turned the computer off. (Although I didn't leave the computer on for more than a few seconds)
Now I don't get any beeps at all.

The Gigabyte board only has two CMOS reset pins. To reset, you can get a jumper (I used the one from the old motherboard) and fit it on for a few seconds, then take it off.
 
Progress:
Based on the above (continuous long beeps = graphics card), I took the card out and plugged it back in, screwing it in until it could barely move.

Turned the computer back on and I got some life out of it!
It seemed to boot (even the CPU fan was spinning for a bit) and I got a single short beep. A couple seconds later, the system restarted, and I get a single short beep (almost as if the boot was successful) and then a continuous beep that doesn't stop until I turn it off.

If I turn it on, the same thing happens. Nothing appears on screen in this time.
 
I found my old graphics card and plugged that in (X1800XT). No change, same result when I turn the computer on. I also tried booting after removing all of my RAM to see what happens. I got the standard short consecutive beeps, so I guess the RAM and the graphics card aren't to blame here, either.
 
I thought maybe the previous user of the motherboard had overclocking settings turned on, so I tried resetting the CMOS again, this time touching the contacts with a screwdriver for a couple seconds. I decided to use just a single stick of RAM, and the system POSTs fine. I went into BIOS and reset everyting to default. It turns out the last person to use the motherboard had set a FSB of 400MHz, but when I set everything to default it goes to 266MHz. I have no idea why using the jumper didn't reset the CMOS the first time :/

However, one problem still isn't solved. The damned CPU fan won't spin, still. I disabled all "smart fan controls" (according to the manual, disabling this in BIOS means the fan runs 100% at all times) however the damn thing still won't spin.

It spins for a split second when I turn the power on, but stops. Any ideas? I am totally lost here :(
 
It's not strictly speaking a solution, but you could connect the cpu fan to a different header or directly to molex. It won't spin down as nicely, but then a constant whine can be less annoying than a variable one.

My hunch is that your motherboard is on the blink. CPU fan header misbehaving and cmos reset not quite working the first time suggest this at least. Gigabyte are good at customer support though, so hope is not lost.

If two different fans fail to spin up from the header, but either work fine when fed 12V normally, that's fairly conclusive. It's possible it'll spin up again if you let the chip heat up, but that's a risky test. The E6600 wont give a damn, but if the motherboard is struggling a bit it may just see it off.

Best of luck
 
Now just before you posted that reply I had tried one thing:

Since SYSFAN1 and CPUFAN both use 12V, I decided to swap them. Up until this point, the SYSFAN1 (a fan on the side of my case) had been working fine.

When I boot, the fan in my case (which is now plugged into CPUFAN) spins! The fan on my CPU (now plugged into SYSFAN1) doesn't.

Since this fan is a brand new Arctic Freezer 7, could it be faulty?
Another annoying thing, the only reason I bought this brand new fan (I bought it this week) is because my existing Freezer 7 wasn't spinning. Is there something special about Artic Freezer fans which means they won't spin?
 
If the new fan won't spin up from any header it's not looking good for it. Can you connect it directly to the psu, or to a different motherboard?

It's possible that there's a compatibility problem between freezer 7s and the motherboard, but it seems very unlikely. They're probably four pin pwm fans, which are intended to spin slower than normal 3 pin fans without stalling. So if anything they're more likely to start on a lower voltage.

I've had one motherboard that didn't spin up cpu fans whatever I set in the bios until the chip warmed up. A friend of mine has a G45 Asus board that not only waits for the chip to be hot before starting the fan, but also throws errors on boot if the fan isn't spinning. Endless amusement there. So these things do happen.

So it may just be a false alarm. If you leave it idling in the bios for a while with a finger on the heatsink, turn it off if it feels like it might burn your finger, otherwise look to see whether the fan starts up then. Not looking good for your freezer though.
 
I connected the fan to a 3pin molex adapter and it didnt spin.

I changed an option in the BIOS in the meantime - I changed the smart fan control to "enabled" and the method to "PWM" (other options are auto and voltage). Upon next boot, the fan was spinning correctly.

I then went into BIOS to re-enable the warning beeps if the fan fails, reboot the system and... suddenly the damned fan won't spin. So, to recap:

- The motherboard seems fine because when I plugged some generic fan into CPUFAN, it spins.
- The Freezer 7 fan clearly can work, since I managed to get it to work 20 minutes ago.

Put the two together, and suddenly nothing is going my way. I just don't know what to do. I bought the motherboard from the MM a week ago from a decent seller and the fan is brand new from OCUK.
 
Progress:
I decided that the brand new fan couldn't possibly be broken so I unplugged it and plugged it back in, making sure I shoved it into the socket securely :p

The fan started spinning! I left the BIOS running idle to see if the temps stayed low... after a minute or so the bloody fan stopped spinning. Maybe the connector is loose.
 
Let's get this straight.

The machine now posts and you can get into the bios....correct?
When powered on the chassis fan spins up?
but the heatsink fan is playing silly buggers no matter what header its plugged in?

If the answer is yes to all of these then remove the fan from the heatsink and replace with your chassis fan. If the heatsink now works it's clearly the fan thas borked. replace with a fan that has a 3pin header
 
Pretty much right. Fans plugged into the 4-pin CPUFAN socket into the motherboard work, unless they are the Arctic Freezer 7 fan (the old one I replaced doesn't work, neither does the brand new one)

That said, I just turned the PC on again and the fan worked for a couple of minutes then stopped working. I just can't figure out what is wrong with the bloody thing. I'm going to phone Arctic Cooling and see if they have any ideas, unless anyone here knows something I don't ;)
 
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