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Coccyx
25-07-2012, 12:12 PM
I'm having the strangest monitor problems. They started around a month ago: when I first turned my computer on, after a few minutes there'd be some flickering in the back ground followed by a complete black screen. I could fix this for the rest of that session simply by turning it on and off again. This has got progressively worse until currently, where, interestingly, after around 15 minutes now, It'll have a ten minute spree of turning itself off. I've also found it turns itself off when alt-tabbing between certain games, usually one's that don't alt tab very well - Dark messiah of might and magic is the most recent one.

So, what do you think? Is it the monitor or my graphics card? Which is worse??

Hunchback
25-07-2012, 12:42 PM
Try plugging another monitor in and reproducing the same conditions (alt-tabbing, etc). That or install an old GPU and try it on your monitor. That would be the best way to pinpoint the problem.

As for which is worse - it depends entirely on your setup. If you have an 24'' LED monitor that costs 1k or you have the latest gen of GPU that goes for 800 euros... Also if some of your stuff are still under warranty or not, since in any case i don't believe either of them can be repaired and they will require replacing.

djbriandamage
25-07-2012, 04:15 PM
I'm having the strangest monitor problems. They started around a month ago: when I first turned my computer on, after a few minutes there'd be some flickering in the back ground followed by a complete black screen. I could fix this for the rest of that session simply by turning it on and off again.

...

So, what do you think? Is it the monitor or my graphics card? Which is worse??

Which do you turn off and back on again - the monitor or the PC?

Which is worse? Whichever one would be more expensive to replace.

Coccyx
25-07-2012, 08:17 PM
It's the monitor that I turn off, and it only takes a couple of seconds each time. In all honesty dragging out an old monitor or fiddling with another GPU sounds more trouble than it's worth - if things get worse I'll see what I can do.

I wonder, could it be related to overheating? That wouldn't make much sense in that playing high demand games doesn't cause the problem, but I am seeing peaks of 80C with my GPU and 65C for my processor.

Feldspar
25-07-2012, 09:52 PM
Er, no, those temperatures aren't excessive.

Sounds like either
1) your monitor is not reading a signal from your graphics card, so it goes on standby until you reinitialise it
2) the signal from your graphics card is dodgy
3) it's a power thing in your monitor
4) your monitor cable is dodgy

This is why people have suggested switching monitors to make sure that the problem is there, this sounds the most likely.

byteCrunch
25-07-2012, 10:35 PM
Have checked if you accidentally turned on the an off timer, I know on my monitor I have it set up to turn off the monitor every couple of hours in case I happen to be away, this is not a screen save it is a setting on the monitor itself, try checking if you have a similar setting.

Otherwise I would suggest it is more the likely a loose power/dvi cable.

Scumbag
25-07-2012, 10:44 PM
Hum... I've been getting a similar problem actually for roughly the same period of time.
What GPU are you running?

Boris
26-07-2012, 09:34 AM
You you use the DVI connector, or are you on the VGA one?

Boris
26-07-2012, 09:35 AM
Nevermind, double post.

Scumbag
26-07-2012, 11:08 PM
I change the question to the OP (if still there)
Is the monitor Samsung branded, and if so how old?

Boris
27-07-2012, 08:06 AM
You're thinking blown capacitors? Also possible.

Coccyx
27-07-2012, 11:48 AM
Still here, the monitor's a Hannspree HF257, linked via VGA. My graphics card is a gtx 550 ti.

Scumbag
27-07-2012, 12:13 PM
You're thinking blown capacitors? Also possible.

Yeah. I used to work in an electronics shop and the number of Caps we sold for dead Samsung PSUs was rather scary considering Samsung's premium.
While Coxxyx has stated its not a Samsung there is still the potential its a capacitor problem by the sound of it. Not sure what to advise beyond cracking the thing open and checking if the PSU has any bulging ones at all.

Shooop
06-08-2012, 03:59 AM
It sounds like something in your monitor is shot.

I had one that intermittently turned itself off while I was using it, but none of the other things you describe.

Do you have a spare to try and see if it does the same thing?

scorpion_wins
06-08-2012, 07:10 PM
This is a long shot, but is the monitor plugged into a power strip? I had a problem whereby my monitor would turn itself off when plugged into one, but direct into the wall it's been on for months no problem.

Coccyx
26-08-2012, 11:14 AM
Update: It's definitely a problem with the monitor. Swapping the input from hdmi to vga (PC to Xbox) results in it turning off about two times. If I swap to the xbox in the first ten minutes, when the monitor behaves normally, I go through the 15 minute period of turning on and off just the same as with the PC input. It's worth mentioning that when it turns itself off, the screen simply goes black rather than the power light blinking out. I actually have to double press it.

neema_t
26-08-2012, 11:26 AM
Sounds like blown caps to me. I had a similar-ish problem (it was really the opposite) where my monitor would flicker before stabilising, I never had it black out after it was 'fully on', though. It was a Samsung 226BW. When I first pressed the power button it would stay black for ages, then get a little brighter, then when it reached the proper brightness it would start strobing very slowly (this was when it was as bad as it got, it was much less severe initially). The strobe rate picked up exponentially until it was like a rave going on in front of my eyes, and it was that exponential...ity that made me think it was the caps; look at an RC time constant graph and you'll see why.

Luckily it's quite an easy fix, it was just five electrolytic caps (in my case anyway) and now the monitor is fine. I bought some pretty expensive caps so hopefully the cathodes will go before the caps do again.

So yeah, in your case, I'd say it's caps because:
- If it were the power supply, it wouldn't stay on; you have to press the power button to turn it off and then press it again to turn it on so the power supply still works.
- The LCD and the processor for it still work because the monitor works when it... Er, works.
- The backlight isn't blown because it works, it just stops working after a while.
- If it were something more sinister than caps I would expect it to have just stopped working, never to return.
- You said it's gotten worse than when it first started, indicating that the caps have been leaking electrolyte fluid, thus losing capacitance over time.
- It's repeatable, predictable and follows a set pattern.
- It involves flickering; caps are often used for filtering frequencies and such so a faulty cap means faulty frequencies.

Coccyx
26-08-2012, 09:29 PM
You've built a pretty convincing case there neema - thanks! Now, how to go about replacing the things... I've very little experience with taking things apart and fiddling with their insides. Have you (or anybody else) any advice on how to go about it?

trjp
26-08-2012, 11:23 PM
You've built a pretty convincing case there neema - thanks! Now, how to go about replacing the things... I've very little experience with taking things apart and fiddling with their insides. Have you (or anybody else) any advice on how to go about it?

Unless you're a electronics expert, forget about it completely.

"Blown caps" is a trendy solution to many PC problems and if you had a multimeter and the knowledge to check all the caps then you might be able to identify and replace the faulty ones - or you could replace them all I suppose - BUT it's a fiddly and skilled job and not a DIY task by any means.

Even if you just have to buy a decent soldering kit and the spare parts you'll be out a chunk of money which I think would be better spent on a new screen (unless you hanker to learn electronics the hard way!?!?)

There are very, very few places who offer that sort of service either - because it's time consuming and a repair will often outweight the cost of a new monitor (when they start at 60 especially!)

Unless your monitor has some warranty left (have you checked??) I think it's time for a new one. If it's faulty with more than 1 input then you can be reasonably confident your PC isn't the issue at least.

Shooop
27-08-2012, 05:02 AM
If it's blown caps, forget it. The capacitors have already leaked and ruined the entire circuit board. There's no way to salvage it if that's what's wrong with it.

neema_t
27-08-2012, 02:23 PM
Unless you're a electronics expert, forget about it completely.

This is true. The caps that aren't dead can quite easily kill you (bolded because I'm really not joking), and the power supply is working fine which means there are a number of high voltage, high capacitance caps which are still alive. In fact even the caps that are leaking could still be very dangerous. So yeah, forget about it until you've tried everything else.


"Blown caps" is a trendy solution to many PC problems and if you had a multimeter and the knowledge to check all the caps then you might be able to identify and replace the faulty ones - or you could replace them all I suppose - BUT it's a fiddly and skilled job and not a DIY task by any means.

This is not strictly true; a multimeter can help but blown caps can be visually identified 99% of the time by their bulging tops or leaked electrolyte fluid, which is a thick, brown congealed mess. Replacing them is easy though, it takes maybe 20 seconds per cap. Silver solder is fucking crap (but necessary because of RoHS rules), fortunately all you have to do is heat up each 'leg' (lead) of the cap, add some fluxed lead solder on top of the silver, then alternate heating the legs while pulling and wiggling the cap away from the board. Then just drop the new cap in (making sure you have the polarity right) and use lead solder on it, snip the excess lead off and that's it... If they're SMD electrolytics (unlikely), it's harder but still doable with a normal iron, assuming you can see and reach the pads of course.


Even if you just have to buy a decent soldering kit and the spare parts you'll be out a chunk of money which I think would be better spent on a new screen (unless you hanker to learn electronics the hard way!?!?)

Any old soldering iron would do, caps aren't sensitive enough to short-term heat (heat is quite often what causes them to die, but only if it's sustained for a long period of time (like, years)) to worry about... You should see the shit we have to use at college! The caps, however, can vary from cheap shit that you'll have to replace again in two to three years or high quality stuff that should last five to six years, if not more. The cost of my repair was about 15 and even that is because the place I got my caps wouldn't let me buy just two caps, I had to buy five of one value and three of the other two for some reason. Then again my monitors were 220 when new so replacing them would've been a real shitter.


There are very, very few places who offer that sort of service either - because it's time consuming and a repair will often outweight the cost of a new monitor (when they start at 60 especially!)

Unless your monitor has some warranty left (have you checked??) I think it's time for a new one. If it's faulty with more than 1 input then you can be reasonably confident your PC isn't the issue at least.

No arguments here, getting a professional to do it would make it a pointless endeavour. I'd be very surprised if the caps were so cheap that they blew within the warranty period but I have been surprised before!


If it's blown caps, forget it. The capacitors have already leaked and ruined the entire circuit board. There's no way to salvage it if that's what's wrong with it.

I've never seen electrolytic fluid leak that much, it's very viscous to begin with and dries quickly in air. I've never seen a circuit board ruined by leaking electrolytic caps, I suppose it's possible but very unlikely, unless, I suppose, the electrolytics are bizarrely mounted parallel to the board instead of perpendicular as you see in pretty much every single board ever.


Basically, if you don't know what you're doing there is a possibility that you will kill yourself using the monitor's power supply caps. I'd recommend exhausting all other options before deciding to do it yourself, and if you do decide to do it yourself Google the shit out of safe capacitor discharging, leave the monitor unplugged for at least a week (caps don't hold their charge for too long when not powered), watch YouTube guides, update your will, tell your wife/girlfriend (maybe?)/husband/boyfriend you love her/him then try it. It is not a triviality and I'm really not joking. Sorry but that's just how electricity is.

If you're out of warranty you could also try finding a local college that teaches electronic engineering or a vocational electronics repair course, they might be willing to repair it for you for free or cheap if a student can learn something, you never know. Or you could ask a student if you could pay them to do it, who knows?

Oh and if you're wondering about my sources and experience, I'm only a BTEC student but I can promise you you'd hear the same advice about working with caps from pretty much anywhere.

harhis23
28-08-2012, 01:10 AM
Had the same problem once, it was my Samsung monitor that started flickering. Since I was a loner and extensive gamer (not a techie guy) I made assumptions it was the monitor which has the problem. I immediately bought a new one and the problem disappeared. So, it could be the monitor. :)

DeadPanda
30-08-2012, 07:29 PM
This happened to me once, the brightness would flicker, and the monitor would sporadically turn itself off. It turned out there was a bloody massive spider living behind the bezel whose little spider feet kept touching the internal sensors for the buttons.

So, if it's possible to remove it on your monitor, it might be best to check behind the bezel. I'm not even kidding, this really happened.

Alex Bakke
30-08-2012, 11:08 PM
Unless you're a electronics expert, forget about it completely.

"Blown caps" is a trendy solution to many PC problems and if you had a multimeter and the knowledge to check all the caps then you might be able to identify and replace the faulty ones - or you could replace them all I suppose - BUT it's a fiddly and skilled job and not a DIY task by any means.



It's 'Trendy' because a lot of the time, it's the cause of the problem. At least, definitely with monitors. They're quite easy to identify, they'll be leaking/swelling at the top. It's not at all fiddly, either - all it will take is the rudimentary knowledge of how to solder/unsolder components. Maybe 10 minutes to learn and practice? That's how long it took me in GCSE Electronics, anyway.