Computer Wont Turn On

[Sczee]

Hi all,

In January of this year some of you on this forum helped me build my current computer and it has worked perfectly (within reason) since I first put it together. However I was fiddling around with the sata cables and one of the fan connectors last night and now it will no longer turn on . My components are listed below:

CPU - E6600 with Thermalright Ultra 120
Motherboard - Asus P5B Deluxe Wi/Fi
Memory - 2x1GB Corsair 6400C4 & 2x1GB Corsair 6400C4D
PSU - Corsiar 620HX
Gfx Card - NVIDIA - 8800GTX
Sound Card - Creative XtremeMusic
HDDs - 2x Seagate 7200.10 320GB & 1x Seagate 7200.11 500GB
Case - Lian-Li V2000 Plus II (Black)
Optical Drive - Pioneer DVR-212
OS - Windows Vista Business (32 Bit)

The CPU was overclocked to 3.24GHz before I turned the computer off to move the sata cables etc. but the core temperatures were only around 60-65 degrees C with Prime 95. The motherboard is still getting power as its 'ASUS' light still glows when I turn the power on at the PSU and some of the USB ports appear to work (the lights on my mouse light up). I havent tested all the USB ports yet. However pressing the power button on my case does exactly nothing. The power/HDD LEDs don't light up, no fans start, nothing happens at all as far as I can tell. I recently purchased the 500GB HDD and the 2GB of 6400C4 but I have had that installed for a few days with no issues. Also I have tested the CPU up to 3.6GHz in the past and while it was hardly stable it still did boot so I doubt my overclock is the problem.

Any suggestions on what I could do/test would be greatly appreciated. I have the money to buy a new motherboard or CPU or whatever if I can be sure that is the problem but I dont have the money to haphazardly buy new parts until it works again. Also as this was my first self built computer I don't have a whole lot of spare parts lying around to swap in for testing purposes.

Im thinking the only things which would stop it from booting altogether are the motherboard, the PSU, the CPU, the RAM or possibly the Gfx Card (?). Although since the fans don't even start to spin up that kinda suggests the motherboard to me (me = inexperienced with these kind of things though). As an outside chance maybe (hopefully) its just the power button on the case which is broken. Is there a way to boot the motherboard manually without using the button?

Thanks for any help.

 

[robisbell]

what do you mean "within reason", that tells me there was issues even then.disconnec the power to all the HDDs, optical drives, and remove all addon cards except for the video card, then try booting.

 

[Sczee]

Originally posted by: robisbell
what do you mean "within reason", that tells me there was issues even then.disconnec the power to all the HDDs, optical drives, and remove all addon cards except for the video card, then try booting.

What I meant by that was just that I have had a few vista driver issues (creative...) nothing hardware wise. Ill try what you suggested when I get home. Would a faulty ram module cause this problem? I could try each of the four 1GB modules i have individually as well just to make sure that isnt that problem.

Thanks for the reply.

 

[robisbell]

it might, but I want to check them in steps, so there's no doubt as to what the issue is.

 

[Sczee]

Ok after swapping a few parts back and forwards with my flatmate's computer I have verified that the power supply is still working perfectly. I believe that this leaves me with either the motherboard or the CPU at fault. Since pressing the power button does absolutely nothing at all (no fans starting up, nothing) I'm pretty sure it must be the motherboard. I have never tried booting without a CPU installed but I assume the motherboard starts up then starts beeping or something.

If there are any holes in my logic please let me know as I plan on RMAing the board as soon as possible. I did by the way, remove every component but the board, the PSU, the CPU and a stick of RAM and this didn't help the problem.

Thanks for any replies.

 

[robisbell]

well, you skipped ahead, you're going to have to rma one and see and then the other if the 1st does not work.

 

[w00t]

sounds like the power supply to me

do the paper clip trick

edit: after, reading that you said you tested it and it works fine

maybe you unplugged the button on accident or button is broken like you said in that case you could check out the switch to see if it's working properly, although it seems unlikely

motherboard could of been damaged from static electricity when you were messing with cables

in the end you diagnoses seems fine psu or motherboard

you've reset your cmos right?

 

[Sczee]

I have reset the cmos but I'm doubtful that was the problem anyway seeing as I had booted with those settings a couple of times already and it worked fine. The button is definitely plugged in properly and I tested booting just by shorting the power switch pins and that didn't work either so its not the switch. So I'm down to either the motherboard or CPU. Would a faulty CPU cause the motherboard to completely not boot (eg. no fans or anything)?

 

[Sczee]

Ok I replaced the motherboard with an Asus P5K Deluxe and everything works again (except for constant driver related BSODs but I just need to format to fix that). Gonna ebay the P5B Deluxe which broke once I get it RMAd.

Thanks for the help sorting this out people.