new system build

[hitz]

I have just built a new system but have a problem.
When i switch on the power - it powers up , fan case spins, and cpu fan kicks in after 1 second but then it all switches off again after 3/4 seconds. Then it starts up again and repeats the process again and switches off again. constant cycle. I have connect speaker and hear no system beeps to indicate a component fault.

I have removed all components and just had mboard and cpu/cpu fan plugged in and i get the same problem so it can be any of the memory/ hdisk.

I have checked that cpu fan power is installed correctly, and both atx and atx12v(4pins) power is securely connected to the mother board.

Any help / advice.
I have tried everything.

My spec is below

gigabyte ga965pds4
intel due core 2.13ghz
dabsvalue case : quicklinx: 3V33WS mfr#: 8032-C4
corsair 2x512mb memory
160gb sata2 w.digital hdd.

[evil bill]

are you absolutely certain the heatsink and fan are seated properly with the appropriate amount of thermal compound on it. It could be something as simple as the CPU overheating and switching itself off to preserve itself.

[acousticlemur]

have you tried resetting the cmos? or pulling out the battery? or both?

[hitz]

im pretty sure the cpu and heatsink are in properly - i can try remove cpu/heatsink but i wanted to leave this as last resort as the heatsink plastic gromets are nice and firmly secured and it was proving difficult to undo this.

I was a bit afriad of damaging the mboard.

What is thermal compound. The instructions on the cpu didnt mention anything about this.

Would the cpu heat up so quickly with 3 seconds of powering on ?

[mullered07]

have you made sure the motherboard risers are in the right place and none are in places they shouldnty be, possibly touching a part of the motherboard it shouldnt be and shorting somthing, ive done this before

best thing to do if you just cant figure out whats going on and have tried everything is to completely remove evrything, just do it again and take your time, putting the risers where they line up with your mobo screwholes, and carefully put everything in one by one, i find rushing my nice new systems usually ends up in a result like what your describing and although i want it up and running NOW lol i take my time now and enjoy it much more lol

[hitz]

Should the system power up and stay powered if i just install the motherboard, attach the 2 power connectors (ATX and AT12V(4pin)) and CPU/ heatsink and then just attach the front panel jumpers (power switch, led switch, speaker, hdd led)

I did this before but thought maybe it needs full system to be built so i setup the hdd and the memory and graphics card - and that resulted in the same problem.

Is it likely i have faulty mobo/ cpu ???? i hope not.

When i put the power on, the power supply fan spins, cpu fans spins approx 1 second later, then after about 5 seconds(repeatedly) the cpu fan switches off first before power supply fan stops. Does this most likely point to cpu/heatsink incorrect installation ?

[mullered07]

like i said ive had the same problem before where ive put a mobo riser in the wrong place and its been touching the motherboard and everything turns on, fans,drives etc but no signal to monitor, its worth taking a good hour to completly strip it down, and start again. check and double check everything a lot of the times its a small DOH kinda mistake thats easy to miss.

[evil bill]

Originally Posted by hitz

What is thermal compound. The instructions on the cpu didnt mention anything about this.

straight from Wiki

Thermal grease's primary purpose in electronics is to mediate small surface imperfections between an integrated circuit (also known as a chip) and a heat sink. When applied in appropriate quantities, it fills the tiny pits and grooves — particularly on today's CPUs — thereby increasing the amount of surface-to-surface contact with the CPU. Without thermal grease aiding the heat sink, CPU power dissipation overheating can occur and will generate logic errors as the heat raises electrical resistance on the multi-nanometer wide circuits.[1]

Many Heatsinks come with a Thermal Pad rather than a tube of compound/grease so even if you haven't done it yourself it doesn't mean its not there. Can you remember seeing a pad on the heatsink? If there wasn't one this may be your problem as CPU heats up pretty quick

[acousticlemur]

do you have another power supply? it is wierd that the power fans turn on before the cpu fan. they should all turn on at the same time. and yeah it should power up with only CPU and Ram on mobo.

[hitz]

unfortunately - i do not have another power supply to hand.
I have removed everything - reseated cpu, heatsink etc and i get the same problem.
Also took mobo out of case and re fixed and tested it - still same problem.
i am really stcuk.

any advise please what i do next to diagnose which is faulty - if any.
If its the mobo - how can i tell if its short'ing.

[Joshmcmillan]

Return it. I had some broken ram once and that's what it done, power up then turn off. Also it does that if the video card is broken, or the cpu, or the motherboard. lol. Sorry.

[Joshmcmillan]

Oh yeah, Forgot about the PSU. It can also cause this problem. lol.

[Joshmcmillan]

The only thing that can't cause this problem is....hmmm... I think even case can because the cables from buttons at front could be broken etc... HDD's can't do that, either can floppies or dvd/cd drives. Sorry but I don't think there is any way to test what's wrong. Mabey try an older system on the psu and try the ram in a different system? Mabey someone you know has a computer with the same ram slot?

[Scavar]

You might want to try running the entire thing outside of the case. Sometimes a case can cause shorts, which could possibly cause the system to restart like that. Otherwise remove the CMOS battery for a good hour and try again.

If all else fails, RMA the motherboard?

[hitz]

ok - motherboard RMA'ed. New mobo in place - same problem.
When i take cpu out completly - with just power feeding to the mobo - power supply fans stay switched on. As soon as i put in cpu and heatsink - powers up for 3 seconds and cuts out. This cycle repeats.

I have checked, double checked, triple checked cpu is in correct position with gold triangle in correct position and correct cutout slots matching. Am i doing something wrong.?
Or do i have a faulty cpu ? how can i tell. this is so fustrating. I have built many pcs before and never had these kind of problems.

I have checked the gold contacts on the cpu - and they all look fine to me. I mean their are no pins to bend - they are just gold contacts - so i would have expected the cpu wouldnt be the problem - but maybe im wrong.

Please help.

[Scavar]

It sounds like an overheating issue. You need to read up on Thermal Compound and make sure you have some on your heatsink. Also triple check that your CPU can work with that motherboard.

If all else fails, try and get another CPU :|

[Joshmcmillan]

Is the CPU new enough to rma?

[Joshmcmillan]

Have you been putting thermal grease on the cpu every time you put it on?

[evil bill]

Have you checked the BIOS doesn't need updated for the particular C2D you have? Its a 965 chipset so it shouldn't really but it s worth checking