System has power, won't post. Some times.

[k4el]

I've been having this issue off and on for about 2 months now. It's getting to the point where i'm sick enough of it i want to take the time to fix it. Lazy i know...

This system has been together for at least a year. So this isn't DOA hardware or something. The problem occurs unpredictably and the system functions normally once it manages to POST. It may be my imagination but it seems to post after i've moved the case or smacked it out of frustration.

My system will power up, all my fans and leds come on. The HDs spin up, and stay spun up. My monitor stays in standby mode because it isn't getting a signal. No system diagnostics beeps can be heard.

I'm stumped, i can't figure it out. Nothing i can think of would occur so unpredictably. My next step is component by component trouble shooting but i'm hoping some one here may be able to save me the time. Given the unpredictable nature of my issue trouble shooting each piece of hardware could take a LONG time.

Any advice?

System spec from memory, i'll get details if needed.

Vista Ultimate 64
MSI p6n SLI (650i??) MB
E6600 CPU
4 western digital Hds. 1 IDE, 3 SATA 2 of which are raided
Rosewill 550watt PSU
4gig memory (i'd have to look to remember brand, think Kingston)
EVGA 8800 gts 320mb


Edits:

I suppose i should have mentioned earlier i borrowed a diagnostic card from a friend of mine. I had it in place when the problem occurred and it displayed nothing, no error code what so ever. So the MB isn't even getting to the start of the post process i think. I'm hoping that eliminates the MB as a source, but i'm quickly getting to the bounds of my knowledge.

I should also mention that i leave my computer on for days or weeks at a time. With no problems what so ever. It would seem strange to me then that it was a fault of the MB, CPU or RAM as i would expect these faults to interrupt long term operation. Then again i'm no expert. Leaving my system on for such long periods is part of why i havent bothered to fix this before, it simply didn't effect my use of the machine and it took quite a bit of time for me to identify this as a consistent issue instead of a one time problem.

 

[GhislainG]

If it boots after you smack it, then you either have a loose connection or a short circuit (not very likely). Check all connections to make sure they're tight and verify that no wire is loose in a connector, i.e, veryfy that all wires are inserted properly on the 24-pin as well as the CPU connectors.

 

[doormatderek]

Could be just about anything going out. First thing I would think is the powersupply, but I would first try 'reseating' everything, including power connections, except the cpu. Maybe something has come loose with all the abuse

oops, beat me to it

 

[Spitfire7]

Bro, maybe this will help. I am going through the same issue. Have a look. http://www.tomshardware.com/forum/259475-31-calling-master-computer-technicians-before#t1881641

I did some tests and am getting close, but see if you can learn anything from my thread.

When you turn the PC on, do you get two yellow lights or Green and yellow? Also, if you turn on the PC and let it sit for 10 minutes will it eventually boot up?

 

[k4el]

Bro, maybe this will help. I am going through the same issue. Have a look. http://www.tomshardware.com/forum/259475-31-calling-master-computer-technicians-before#t1881641

I did some tests and am getting close, but see if you can learn anything from my thread.

When you turn the PC on, do you get two yellow lights or Green and yellow? Also, if you turn on the PC and let it sit for 10 minutes will it eventually boot up?

Thx for the thread. As for your questions. Yes to the first. As for the second I only tried that once and it did not boot up after being left alone for 5 minutes or so. I'll try leaving it alone longer soon. Just to be clear i'm not getting any diagnostic codes from the MB at all. It doesnt even get to that point.

 

[croc]

I've been having this issue off and on for about 2 months now. It's getting to the point where i'm sick enough of it i want to take the time to fix it. Lazy i know...

This system has been together for at least a year. So this isn't DOA hardware or something. The problem occurs unpredictably and the system functions normally once it manages to POST. It may be my imagination but it seems to post after i've moved the case or smacked it out of frustration.

My system will power up, all my fans and leds come on. The HDs spin up, and stay spun up. My monitor stays in standby mode because it isn't getting a signal. No system diagnostics beeps can be heard.

I'm stumped, i can't figure it out. Nothing i can think of would occur so unpredictably. My next step is component by component trouble shooting but i'm hoping some one here may be able to save me the time. Given the unpredictable nature of my issue trouble shooting each piece of hardware could take a LONG time.

Any advice?

System spec from memory, i'll get details if needed.

Vista Ultimate 64
MSI p6n SLI (650i??) MB
E6600 CPU
4 western digital Hds. 1 IDE, 3 SATA 2 of which are raided
Rosewill 550watt PSU
4gig memory (i'd have to look to remember brand, think Kingston)
EVGA 8800 gts 320mb

My first suspect component would be the Rosewill PSU... Not known for reliability, etc. Try an Antec, Corsair, basically any good PSU. Surprised that this hasn't already been noted.

 

[jsc]

croc:
Beat me to it. Try to borrow a better PSU. Rosewill's are about two steps above junk.

 

[croc]

Fair enough, you beat me to the Zylog reference on understanding CPU's ;-) (and I wouldn't give the Rosewill 550 even one step above junk)

 

[k4el]

Ok better PSU is on top of the list now.

If you all don't mind playing a little House (i couldn't help the pun) could i get a differential diagnosis? If it's not the PSU what else is coming to mind?

 

[croc]

2nd guess would be vga card, next would be MB.

 

[k4el]

Mind helping me understand how the VGA would completely prevent POSTing? Not questioning your suggestion as much as i dont understand it.

I'm feeling pretty good about the PSU. It's the second bad opinion i've heard about the brand. Also, when i smack the box to start it up i smack it right on top of the PSU. I may be imagining that... but something tells me it really has been the difference.

 

[croc]

No VGA working, no screen... My system doesn't beep unless there is an issue, so if my card died, I'd not know it posted until I replaced it. I've never had a MSI, so don't know the particulars.

 

[k4el]

Ah, i gotcha. Well my system always beeps a bit at start up. Its not an error code just an acknowledgment. So i am pretty confident its not a display issue because i'm not hearing the normal beeps.

 

[croc]

Go for the PSU, it won't be money wasted in any case. For future reference, www.jonnyguru.com is one of the better sites for PSU reviews.

 

[k4el]

Alright, thanks for the help. I suppose i should have mentioned earlier i borrowed a diagnostic card from a friend of mine.

I had it in place when the problem occurred and it displayed nothing, no error code what so ever. So the MB isn't even getting to the start of the post process i think.

I'm hoping that eliminates the MB as a source, but i'm quickly getting to the bounds of my knowledge.

 

[k4el]

After spending some time with a friend testing things out. I'm 99.9% convinced it's the PSU. Got a new OCZ700GXSSLI 700W on the way. I'ts not an Antec or Corsair but OCZ is a well known brand so i figure it is a safe investment and newegg's awesome after xmas deals help too.

Thanks everyone who helped me out.

 

[Danzki]

Hey, any news on this? I have the exact same problem with my computer, after it has been running stable for a year. Boot up, power to fans and LEDs but no post and no signal to the monitor. (it's hard to know if it actually does make a post, but since there isnt that expected start beep, i guessing it doesnt)

I was half thinking the ram could be the problem, but PSU does sound more likely. Only, I have a Hiper 770W, which I see as a fairly reliable PSU.

 

[Newf]

croc:
Beat me to it. Try to borrow a better PSU. Rosewill's are about two steps above junk.

You are being overly generous...

 

[Danzki]

I just had a breakthrough on this. After reading this article from JohnnyGuru.com (thank you who ever gave me this link), I tried to start the computer with only MB and CPU, and added stuff from that. One of my four ram blocks was the sinner. It prevented the MB from doing its POST (no even a beep).

 

[k4el]

Well, it looks like the new PSU has not fixed the issue. Same odd issue.

Systems powers up, won't post. Fans spin up and stay spun up. Only thing that fixs it is to power down the system, give it a good smack and hit the power button again.

I'm going crazy here! My systems runs great once it is booted up, no issue at all for days on end. My next move is to run memtest even though i really don't think it my memory is the problem.

I recently removed everything from the case and reseated every bit of hardware.

 

[GhislainG]

Something has to be loose, not connecting properly or shorting out. Next time the problem occurs, try to move the motherboard a bit to see if the system will power up without smacking it. The motherboard could be shorting out at one of the standoffs. What case do you have?

 

[k4el]

Link to my Case's Info

I really hope it's a short or a loose connection. I just bought a power supply and buying a new mobo is going to be tight financially. It really couldn't be anything else in my mind, otherwise i would expect to see other problems even while the system is running.

I'll look into buying those insulator rings for the mounting posts and put those on.

 

[GhislainG]

That site doesn't clearly show the internals, but Anandtech fortunately provides good pictures. The posts are screwed in, therefore they can't cause that problem (unless one was installed where the motherboard doesn't have a correspondig hole).

 

[k4el]

I'll double check to make sure i didnt spaz out on the post placement. They've been in the same place for years though, maybe the board has shifted with heat.

I have a feeling i need to budget for a new mobo if i cant nail down this short.

Ghis - you seem to be pretty experienced in this, what are the usual suspects for shorts?

When i borrowed a friend's PSU i couldn't replicate the issue. I'm trying to remember if i had any other hardware unplugged and i'm recalling that i may have only had one of my DVD drives plugged in i'm going to test that later.

 

[k4el]

Well i spent about 2 hours this afternoon trying to figure this out. I realized one specific fan was spinning up and staying at full speed. It was distinctly louder than the others.

I watched the fans spin up and figured out it was my video card's fan (EVGA 8800 GTS 320mb). Since this was odd i wondered if the video card was the issue. I removed it and booted up my system with no video card. The system posted since i could hear the beeps.

I replaced the video card and powered up the system, no post. So wiggled the video card in the PCIE slot, next power up the system posted. I adjust the video card back tilting it towards the top of my case, no post. I tilted it down, post. It was really reliable and i could easily repeat it several times.

Thinking i had found the issue, i took a break and watched some TV. I came back about 20 minutes later and tried to replicated the up and down adjustment but it had no effect as befor. My system would post some times and not others. I unseated and adjusted the video card several times after that. I looked for anything that could be shorting and found nothing.

I may or may not be any closer to finding out what is wrong but right now my system is posting reliably. I haven't had the system refuse to post over the course of several recent attempts. Maybe i worked what ever the issue was out with all my fidgeting.

I'm hesitant to say it is fixed but at the moment i can not replicate the problem.