PDA

View Full Version : Weird Boot Problem



Billy T
28-04-2013, 06:06 PM
Hi Team

A couple of weeks back my computer failed to boot, that is to say, it didn't seem to even start post. The power light came on, there was one brief flash of the drive light, a blank screen, and that was it! I tried again a couple of times with a decent 'all power off' wait period etc, then being outside my knowledge and resources I took it to the guys who built it for me (a very reputable company, and excellent service). Short story is, it booted every time for them over a couple of days, so they update the bios etc and I brought it home. It booted first time and all seemed well so at the end of the day I turned it off.

Next morning it failed to boot again, same symptom, so I turned it off and unplugged the supply, left it for some time and tried again but no luck. Next morning I gave it one more shot then loaded it back in the car and took it back again. This time it was there for several days and never once failed to boot, so it is somewhat mysterious as to what is going on.

It did start first time up when I brought it back here, so in the meantime I am leaving it running 24/7. I have had to restart Windows three or four times because of my scanner problem in my earlier post, and that was a bit nerve-wracking, but it came up again each time, however it was not powered down on any of those occasions.

It is not a power quality issue, because it runs on a full-time online true sinewave UPS with tons of capacity to spare, and it seems to me that it can't be peripherals because it doesn't even get to look for them. RAM or Motherboard seem to be the prime suspects, but that doesn't explain why it fails here but not at their premises. It isn't a drive failure either, because it is a RAID 1 mirror array and has worked through OS disk failures in the past.

I post this in the faint hope that somebody has seen this sort of issue before and may have some ideas. It is very frustrating, and what little work I could do without it was carried out on my ancient W2K Plll 550, which has a bad case of the screen shivers, so is hard on the eyes!

Cheers

Billy 8-{) :confused:

Trev
28-04-2013, 06:43 PM
Have you tried not running it through the UPS ?
:)

fred_fish
28-04-2013, 06:52 PM
+1

Iantech
28-04-2013, 07:17 PM
Short story is, it booted every time for them over a couple of days, .... This is actually pretty common which is in many cases why I like visiting the computer on site when problems like this arise. It is often because when it is on site, there are other factors added to the equation, such as a USB printer, scanner, webcam, UPS conection cable, etc etc. Easiest thing to do, is unplug everything (apart from keyboard, mouse, monitor of course) and see if it boots fine , if it does, then plug them in one at a time and see what is causing it. That would be my start point anyway.

coldot
28-04-2013, 08:58 PM
Just a thought..... Do you take PC to fix-it guys with mouse, keyboard, monitor and all other peripherals? Or are there some things that stay at home and are plugged in again when the PC comes home?
I had a similar problem once with USB legacy connection.

wainuitech
28-04-2013, 10:54 PM
Another possible cause can be a heat related problem, or more to the point, a lack of it.

Seen this happen several times, when the computer is warm ( once its been running the first time) it doesn't play up again till it cools down completely.

I have had a customers computer here on several occasions trying to track down the exact same problem.

When it was cold ( off over night in the workshop) it wouldn't boot, BUT once it booted as soon as the air temp warmed up it was fine for the rest of the day.

The air temp early morning was enough to cause a fault in the power supply to fail, as soon as it got slightly warmer ( around 8.00am) the damn thing booted fine. I brought the PC into the lounge where its warmer ( much to the Grrrrrr of SWMBO), and it was fine the next morning ( around 7 am), back outside over night where its colder ( workshop) wouldn't boot at the same time the next day.

Took ages to find the faulty part as you had one shot each day, but got it in the end.

Try changing the Power Supply as a simple test first.

Billy T
29-04-2013, 01:08 PM
Okay

Thanks for all the info and advice provided so far.

At present I am leaving the computer turned on, but due to my scanner problem I had to 'restart windows' several times. I noted that this seemed to take me back to pre-post, because it comes up with the usual motherboard splash screen, then goes through the RAID screen etc before finally booting into Windows. Apart from not powering down completely, this seems to be pretty much what I would see from a cold boot.

Is that the case, or is it post-post (so to speak)?


RE USB, for as long as I have had the computer, if I move it at all, I hear a USB connection drop out, then it restores. I think that is a lead/plug issue but it has not been a problem other than the annoyance. Incidentally, I do not use the front panel USB outlets because I am aware that they are not reliable, and they did give me problems. I think I may have USB3 outlets as well (unused) are they red? I just noticed them this morning and they are on an IEEE1394 (firewire) sub-board with a USB symbol above them. Seems pretty conclusive!

In terms of USB loading, I have three printers (HP mono and Samsung colour lasers and a Canon Inkjet) Canon scanner, and a mouse, plus a multi-outlet USB hub. I don't recall what is on that, but it will be one or two of those items. Only the Mouse and HP printer are normally active, or were active during all of this, the other items are usually switched off.

Mouse, keyboard and monitor are on a mechanical KVM switch to allow (very infrequent) access to data and programs on my old W2K computer (XP does not allow print screen from DOS windows). Mouse is USB but connected via a USB to Mini-Din adapter, keyboard is native Mini-Din. This setup has been 100% reliable (up until now).

Temperature in my office is stable as it is an interior room with no windows, but I put a large glass-brick panel in the wall through to our downstairs lounge, which does have windows aplenty, allowing me the illusion of a connection with the outside world and helping to maintain my sanity!

At this point I can't see what could be wrong with the power supply if it powers up each time and the failure never occurs outside of my office. As far as I am concerned, 230 volts is 230 volts and the only difference betewen here and the tech's environment is that they are in a commercial and heavy industrial area so would have a lot of industrial noise on their power. Looking over from the other side of the fence, I sort these thing out for a living, and if the power supply was faulty, and refused to power system boot over several attempts, then it would display the same problem wherever it was plugged in.

Likewise for peripherals, it worked OK until it stopped (natch :rolleyes:), then it booted again with the same peripherals and that cycle has repeated.

Obviously there is something wrong somewhere, but I can't get a handle on it yet. What I would like to know, and would help immensely, is where I can find a description of the initial boot sequence and what might be scanned for errors etc to prevent boot continuing, so that I can follow up the advice already given with a better understanding of what I might be looking for.


Cheers

Billy 8-{)

Speedy Gonzales
29-04-2013, 01:37 PM
Disable the splash screen in the BIOS. See what its saying on the post screen. Look in event viewer for the time the prob is happening. See what it says. USB3 is blue isnt it?

Also note, NOT all USB devices like or will work if plugged into a USB hub. If a computer doesnt power off properly this maybe a driver prob. It maybe corrupt or incompatible, or something

I had the same prob here, when windowsupdate installed a dodgy / probably corrupt / incompatible driver. It stopped 1/2 way through the install. And the computer wouldnt restart or power off . It hung. Uninstalling / rolling back the driver in device manager fixed it

wainuitech
29-04-2013, 01:42 PM
At this point I can't see what could be wrong with the power supply if it powers up each time and the failure never occurs outside of my office. As far as I am concerned, 230 volts is 230 volts and the only difference betewen here and the tech's environment is that they are in a commercial and heavy industrial area so would have a lot of industrial noise on their power. Looking over from the other side of the fence, I sort these thing out for a living, and if the power supply was faulty, and refused to power system boot over several attempts, then it would display the same problem wherever it was plugged in. Thats what I thought as well. But on the one that I had here, as soon as it booted the first time it was OK again, even if you turned it off for an hour or two, it would boot fine.

It took a while to track down the problem because you had one shot in the morning, if it failed you could change /look at one thing, then when it booted you had to leave it till the next day to see if the alteration was in fact the problem. Checked all the voltages, etc and every thing read as it should. I changed the PSU and it has run good ever since. It was simply a component that when cold refused to work correctly.

May or may not be the case with yours - only saying its a possible option to look at.

I actually had a Dell PC a few years back, wouldn't boot when cold, the owner would press the button in the morning = Dead, I'd go and press it after she called and away it went. That was also a PSU problem, it actually had a dry joint somewhere and as soon as things warmed up everything went perfect. Funny thing was if you gave it a thump above the PSU on the case in a certain spot (literately) it would work as well.

Trev
29-04-2013, 02:42 PM
Now this sounds crazy, but a few years ago on a computer I had every now and then the monitor would go black and the no signal would appear on the screen, for some unknown reason I thought I would try a different PSU which I did, and the problem disappeared.
:)

Rod J
29-04-2013, 03:16 PM
I had exactly the same temperature related problem as detailed by wainuitech.

The colder the weather it would almost always fail to boot on first try. In my case it would cycle between attempting to start/turn off/start again all by itself. It was quite amusing to watch it do this up to six times or so.

On inspecting the PSU it had several bulging capacitors so I knew it was the problem. I replaced the PSU and I've never had a problem since.

http://pressf1.pcworld.co.nz/showthread.php?116900-Cold-boot-startup-problem

Agent_24
29-04-2013, 03:45 PM
I had exactly the same temperature related problem as detailed by wainuitech.

The colder the weather it would almost always fail to boot on first try. In my case it would cycle between attempting to start/turn off/start again all by itself. It was quite amusing to watch it do this up to six times or so.

On inspecting the PSU it had several bulging capacitors so I knew it was the problem.

The marginal\failing capacitors have higher ESR when cold, once they get heated up a bit the ESR drops and things start working again.

dugimodo
29-04-2013, 04:06 PM
Also I've seen this caused by a cell phone left in to charge on a USB port. Flash drives also, USB can cause weird stuff to happen.

I also fixed a dell pc with a dodgy psu that would start and run fine the first time you tried but if you shut it down would not start again until unplugged from the wall and left for several minutes. The psu was not suplying voltage to it's fan either.

You don't mention if you tried without the UPS as suggested? Try to think what is different between home and the shop and eliminate everything you can 1 by 1

Billy T
29-04-2013, 04:09 PM
Thanks People

I have taken on board 100% the peripherals argument and will pursue that line of investigation, it makes good sense to me now. Also, this morning I did some research into booting issues and learned a helluva a lot that I didn't know about boot processes!

I remain unconvinced about the power supply though, because I still doubt that it would fail repetitively here over a number of consecutive startup attempts, but start every time over a week at another site. It is not an el-cheapo supply either, being a business computer, I spared no expense in terms of quality components and it has plenty of load capacity headroom. I did this for my previous three computers, which spanned 18 years of reliable daily use and they lasted very well.

I am well familiar with bad caps too, having repaired several hundred switchmode supplies over the years, though to be fair, not the computer variety. I know that even good quality caps still fail from time to time, but their failure modes are a little different and not quite so obvious, though some may bulge a little. However, only crap quality or seriously under-rated caps bulge in bulk. I test 'in-circuit' with an ESR meter and that shows up even minor deterioration, long before they become problematic.

They bulge because their initial losses (ESR) are higher than normal, so the high frequency ac current they must pass causes internal heating and cooks their electrolyte. This causes their ESR (equivalent series resistance) to rise even further, which causes increased internal dielectic and resistive losses, which in turn generate more heat, which then accelerates the final failure. It is a slippery and exponential slope once it gets started.

Cheers

Billy 8-{) :thumbs:

fred_fish
29-04-2013, 07:24 PM
So just try it without the UPS already ... :D

Agent_24
29-04-2013, 07:58 PM
I would rule out a peripheral problem first. I once had a USB device (old webcam, I think) that went faulty and caused all sorts of problems.

Billy T
29-04-2013, 10:40 PM
So just try it without the UPS already ... :D

Nope, it ain't broke. The UPS is fine, as I said before, it is a professional sinewave full time on-line UPS which means that at all times the computer is running off the inverter, not the mains. It is not a cheapie consumer item, and it is highly unlikely to produce those symptoms at random. I have all the gear necessary to verify that, but I'm not going to bother, it runs just fine. I've monitored the output and it is clean as a whistle and stable as the Bank of England used to be (and that is mirrored in the UPS LCD display screen as well). That sort of gear does not throw random temper-tantrums, they either work or they die in a blaze of glory. I just flicked the power off and it didn't miss a beat, just the fan speed increased a little to ensure it stayed cool.

I think it is more likely a peripheral problem, and I'll look into that once I've caught up with my work, but at present I wouldn't shut it down for love or money.

Cheers

Billy 8-{)

wainuitech
29-04-2013, 11:11 PM
Its actually a very easy fix to find out the problem or at least narrow it down.

Once you can shut it down over night, disconnect ALL peripherals, or at least exactly the same as when it was at the shop. If it still fails to boot then its a power feed problem someplace, the UPS may be top of the line equipment but that means bugger all if there's a fault with the power Supply in the case or a circuit on the motherboard. All a good Power supply is doing is supplying good power, once it gets there all that can change.

Then again it could be like some problems -- for gods sake what ever is playing up, hurry up and fail completely that'll narrow it down 100% :D

Agent_24
30-04-2013, 10:32 AM
Then again it could be like some problems -- for gods sake what ever is playing up, hurry up and fail completely that'll narrow it down 100% :D

Got to love intermittent faults! :rolleyes: