problem turning pc on - Page 1
Forum section: electronics / general

author: sony mavica
author_rank: Frequent Contributor
timestamp: September 16, 2016, 11:02:40 pm
content: anybody know what could be causing this problemthis has been happening for the last couple of weeks or longer when i go to turn my computer on the light on the power button just flashes and the fans in the pc turn on but computer does not boot so i have to switch pc off at the back take power cord out and wait about 1min or so then plug it back in switch it on at the back then when i power it on sometimes it will power on fine other times i have to switch it off again at the back of the pc then on again and when i power it back on the light on the front of power button starts flashing and fans turn on but if i press the open button on the dvd drive once or twice the pc boots as normal and pc will work 100% fineanybody know what is going on i really don't have the money to buy another computer or even buy new parts for this one so hope this problem could be fixedthx

author: bitslice
author_rank: Frequent Contributor
timestamp: September 16, 2016, 11:50:46 pm
content: Google suggest motherboard is faulty.although if you have a friend with a PC you could try using his PSU to see if your PSU is at fault.Try cleaning the PSU, sometimes dust makes them overheat and shut down.To get a PSU to power up without a motherboard, stick a paperclip from the green wire to any black wire.as with most troubleshooting, try disconnecting everything from the M/B including sound cards etc and see if the thing boots.When we know which bit is failing we can suggest a possible fix

author: sony mavica
author_rank: Frequent Contributor
timestamp: September 16, 2016, 11:55:34 pm
content: Quote from: bitslice on September 16, 2016, 11:50:46 pmwill give it a try

author: wraper
author_rank: Unknown
timestamp: September 16, 2016, 11:58:55 pm
content: Most likely electrolytic capacitors in the PSU have died. Don't suggest using it as is. If it is crappy enough, it may fail in a way that will destroy all other hardware in the PC.

author: imidis
author_rank: Frequent Contributor
timestamp: September 17, 2016, 12:20:10 am
content: I'll just share a super odd moment. I had an odd one I've not really seen before. The computer would sometimes turn on, sometimes not, sometimes give a non-existent error code (6 beeps), sometimes not. Turned out to be a corrupt bios. Re-flashed and it was fine. Odd, just always good to think outside the normal issues as well if the normal culprits turn up nothing. PC troubleshooting can be fun sometimes.

author: System Error Message
author_rank: Frequent Contributor
timestamp: September 17, 2016, 12:54:48 am
content: Try this, unplug it, and press the power button for 30 seconds to discharge the entire system, than try. If the issue is still there there might be a short sometime. Ive seen this happen when not using motherboard riser screws with the case.If the PSU failed the system would be unstable rather. CPUs if they fail would prevent booting. Motherboard failure would consistently prevent booting (though the discharge method usually works). I have rescued many computers this way. Thanks to the lax of knowledge on discharging it is one way you can get hardware cheap as people think its broken when its not.Motherboards have lots of components that a failure usually wont stop the boot process, only may cause havoc from OS like getting an exclamation mark in device manager, causing the PC to freeze.

author: Ampera
author_rank: Super Contributor
timestamp: September 17, 2016, 01:08:59 am
content: As an experienced person in computing (I work with a load of old tat in my spare time) I would suggest that the PSU is the first thing to stop using. As said previously they have a bad habit of busting everything else in the system. I don't think it's the CPU not seated, and the motherboard is fine. Those problems would produce symptoms more drastic than working on occasion. Normally if you have a store bought prebuilt machine (Dell is a damn BARON at this) the PSUs are made using the cheapest crap possible. You normally don't even buy PSUs by specs, you buy them by brand and then meet your requirements. People have lost machines over cheaping out on their PSUs. Cooler Master and Corsair are normally reliable brands. Trust me, buying the brand name PSU might seem like money wasted on a name, but it's a name that enlists quality parts and testing into their items.The reason for the partial power on is that the PSU might not be supplying enough power to all the rails, so you get some stuff on, some stuff not. However I could be ENTIRELY wrong (I sometimes am) so try doing everything, Reseating connectors is my first suggestion. Only reseat the CPU if you know what your doing or you have nothing else to try, since they are VERY fragile, and can go thermally wrong if you don't install them proper.Best of luck, I just got done with a 5 day tango with an old PCI/AGP system, that wasn't fun.

author: bitslice
author_rank: Frequent Contributor
timestamp: September 17, 2016, 01:55:15 am
content: Quote from: TwoOfFive on September 17, 2016, 01:08:59 amThey don't actually make their own PSUs, but the various OEM companies that do on their behalf are OK, many have 5-7 year guarantees now.

author: Brumby
author_rank: Unknown
timestamp: September 17, 2016, 02:10:55 am
content: Except for the optical drive trick, you could have been describing the exact same problem I had with my machine.I thought it might have been something to do with the CPU upgrade I did recently - and it was .... indirectly.Before the startup hassles, my 'new' CPU was getting too warm, so I upgraded the cooler to a heat pipe type - fitted an extra case fan and re-dressed the interior cabling to allow for a freer air flow.This ran fine for a few weeks - and then I started getting intermittent problems, just like those you describe. Sometimes a press of the reset button was enough ..... sometimes it was a real pain.To cut a long story short, I found the power header to the motherboard was not properly secured and the clip was not engaged. It seems that when I re-dressed the cabling, the thick harness going to this header put a little too much pressure on the connection and it worked slightly loose.The solution: Simply removing this header, checking it and refitting, making sure the clip was engaged.Over time, the cable harness had conformed to its new position, so the is no longer any undue stress ... and my machine has booted up first go every time since.

author: edpalmer42
author_rank: Super Contributor
timestamp: September 17, 2016, 02:14:08 am
content: I've seen various PCs that either wouldn't turn on or had trouble turning on. In many cases, it turned out to be the power supply, specifically the +5 standby supply rather than the motherboard. If you have a DMM, check the voltage - doesn't matter if the computer is on or off as long as it's plugged in and the power switch is turned on.

author: Brumby
author_rank: Unknown
timestamp: September 17, 2016, 02:14:44 am
content: Murphy will ensure your problem won't be so easy to fix as mine ... but you can always hope he's taken a holiday.

author: Monkeh
author_rank: Super Contributor
timestamp: September 17, 2016, 02:19:10 am
content: Quote from: edpalmer42 on September 17, 2016, 02:14:08 amJust because the voltage is good, doesn't mean the rail is. Honestly, it sounds like the +5VSB rail is good, as the soft-on circuit is working.I'd verify it's actually asserting PWR_OK.

author: sony mavica
author_rank: Frequent Contributor
timestamp: September 17, 2016, 03:00:37 am
content: thanks guys but now it seems when im using the pc since i made this post today and about 4 times i have had a message popup in the bottom right corner saying Nvidia Display driver stopped working and has recovered ectcould the video card be causing the problem

author: Monkeh
author_rank: Super Contributor
timestamp: September 17, 2016, 03:01:36 am
content: It's more likely to be a symptom than the cause.

author: bitslice
author_rank: Frequent Contributor
timestamp: September 17, 2016, 03:12:50 am
content: Quote from: sony mavica on September 17, 2016, 03:00:37 amI've had the same message for months, followed by a bluescreen a few seconds later.Cured it by removing the GPU heatsink, cleaning it, reapplying thermal paste and then adding an external fan.Now I just get the occasional warning, but not the subsequent bluescreen.These could easily be two separate issues.

author: Brumby
author_rank: Unknown
timestamp: September 17, 2016, 05:11:43 am
content: Quote from: bitslice on September 17, 2016, 03:12:50 amI'm inclined to agree.My experience with problematic video cards has been predominantly about heat. With a machine starting up from cold - in the thermal sense - I would separate the two.Then, there is the possibility that theyarerelated, but I'd bet my $1 that they are not.

author: wraper
author_rank: Unknown
timestamp: September 17, 2016, 07:27:18 am
content: Quote from: sony mavica on September 17, 2016, 03:00:37 amIt could be because of unstable power. And display driver will crash because of just any problem in a system, like glitching main RAM. The fact that DVD drive trick helps to start it, suggests that loading the power rails differently, helps to preventing PSU going into protection (voltage rails have shared regulation). Seriously, disassemble the PSU and check if electrolytic capacitors are bulging. Even if you won't kill motherboard or GPU because of unstable power, your HDD may feel very bad about it. The fact that you need to disconnect it from the mains to start again, suggests that internal protection in the PSU kicks in, to prevent frying other hardware. Also, no way you would need to disconnect the power if it was GPU fail, in that case power button is more than enough to start PC again.

author: SeanB
author_rank: Super Contributor
timestamp: September 17, 2016, 08:10:39 am
content: New PSU time for sure. The old one will have bulged caps and split sleeves on some, and they will all be toasted brown. That it fails on turn on says the PSU is failed, not failing, and the video card errors are indicative of a very high ripple on the 12V rail. Change the PSU immediately, before it cooks the rest of the computer from high voltage as it fails out of regulation until it finally reaches 100% on time on the drive side which blows the switching transistors. By then the 5V rail will be at 10V and the 12V rail will be past 30V.

author: daybyter
author_rank: Frequent Contributor
timestamp: September 17, 2016, 09:26:32 am
content: I had a problem with the 5v rail. Attached usb devices stopped my pc from booting. Unplugged the usb stuff and the pc booted just fine.

author: Ampera
author_rank: Super Contributor
timestamp: September 17, 2016, 10:20:46 am
content: Quote from: Brumby on September 17, 2016, 05:11:43 amYou see, I'm not. This now sounds more like a post failure than a power issue. At this point LITERALLY anything can cause a computer to not post. A borked GPU can do that, as I have been dealing with borked GPUs and post failures for the past 5 days (Finally fixed!)But the PC not wanting to post could be PSU, Bad RAM, a bad peripheral on an ATA/SCSI bus, a bad PCI/PCI-E/Expansion card, poorly seated CPU, and whatever else you could think of. Some times these result in a visual or auditory error, but there have been cases with me that a peripheral just decided to not let the PC boot for some reason. Why unplugging it and plugging it back in works? Idk maybe your shaking the gremlins loose. PCs are complicated parts that have required dozens of engineers to even conceive on a base hardware level, and base concepts are still in use fresh from the early 1980s. As a result you can as a computer engineer come up with a logical and likely solution, to find some bugger off part was not in right.My failproof suggestion is to unplug everything inside you do not need to start the computer. No drives, minimal RAM, only a GPU (If you have an iGPU or an APU (Intergrated Graphics) use that instead of a dedicated card, or if you are using that regularly use a dedicated card if you have one), and take out any other expansion cards. The point is to unplug as many things as you can think of in order to eliminate most of the components as possible issues. Then if you have the parts, start replacing stuff. I'd suggest swapping out the PSU first. All of this can stem from bad/unclean power or voltage spikes/drops starting or stopping. PSUs are like suspension bridges. You build it right, it will last for decades, you do not build it proper, like the majority of those on the market, you end up with a magic smoke machine.If you understand how CPUs are installed, you can try reseating it (Or swapping it out, but this is an unlikely issue because it wouldn't run at all of the CPU was in wrong)At this point you can understand one thing. A part is causing the computer to not turn on. This is all you need to know, because you can most likely replace one thing.

author: sony mavica
author_rank: Frequent Contributor
timestamp: September 18, 2016, 02:03:20 am
content: Quote from: TwoOfFive on September 17, 2016, 10:20:46 amthanks since trying what you have said the computer boots fine now well i have only shut down and left computer for a couple of hrs 4 times but every time ive come back to use it has booted up finestill getting the error Nvidia Display driver stopped working and has recovered ect well only had it pop up twice in 4 times i used the pcfunny thing is i played gta v for about an hr and never got the message strange as gta v using a lot of graphics card and also played tony hawks 4 and never got the errormy video card is nvidia gforce gts 450

author: Monkeh
author_rank: Super Contributor
timestamp: September 18, 2016, 02:05:00 am
content: This continues to smell like a bad power supply.You really should try doing something about it sooner rather than later.

author: sony mavica
author_rank: Frequent Contributor
timestamp: September 18, 2016, 02:25:43 am
content: Quote from: wilfred on September 18, 2016, 02:22:44 amits like 4/5 years old

author: Ampera
author_rank: Super Contributor
timestamp: September 18, 2016, 02:44:40 am
content: Quote from: sony mavica on September 18, 2016, 02:03:20 amGlad it all works. Replace what you wish, but a reliable PSU is always a good idea (I know from dear, dear experience).

author: sony mavica
author_rank: Frequent Contributor
timestamp: September 18, 2016, 07:59:00 am
content: my friend came over today and took a look at my graphics card and saw my cpu fan was a little dusty so he took it off but when putting back on he broke one of the clips on it now i can't use that computer till i get a fanso now im having to use a android tv box as my pcmight just have to save up for a new pc and just sell this one for parts i will keep the hdd tho as there is important stuff on them

author: wraper
author_rank: Unknown
timestamp: September 18, 2016, 02:51:41 pm
content: Oh, my. Really, take some piece of wire or whatever and hack the cooler. Or even better, use only 2 holders on opposite sides, should be good enough to work. As you already don't use this PC, dissemble that PSU finally. My guesstimate based on experience is that, with 90% probability, fault is there.

author: Monkeh
author_rank: Super Contributor
timestamp: September 18, 2016, 03:01:45 pm
content: I have a suspicion he means the pushpins.Don't let your friend touch anything again.

author: wraper
author_rank: Unknown
timestamp: September 18, 2016, 03:05:42 pm
content: Quote from: Monkeh on September 18, 2016, 03:01:45 pmI understand that. Also can hack it with using something like screw and nut instead, to make as reliable as it was originally. Upgrading i7-2600k does not make much sense either, especially if don't want to spend much money. Not that much performance will be gained unless buying at least 6 core CPU (CPUs really stagnated all those years). Fix the cooler and buy new PSU to fix the issue (if too lazy to be bothered fixing the old one) and GPU + SSD (if want real upgrade).

author: rdl
author_rank: Super Contributor
timestamp: September 18, 2016, 04:16:44 pm
content: Quote from: sony mavica on September 18, 2016, 02:03:20 amDefinitely get a new video card. Your 450 doesn't even meet the minimum specs for GTA V, I'm surprised it runs at all.

author: Ampera
author_rank: Super Contributor
timestamp: September 18, 2016, 05:25:40 pm
content: Quote from: sony mavica on September 18, 2016, 07:59:00 amIf you want help designing a computer, DM/PM me on the forum or we can email each other (Sorry I need to mask it) 7d65e86a@opayq.com at this address.I think a lot of people here are trying to give you an answer on EE experience instead of computing. If it was working after reseating stuff, I doubt the PSU was the immediate issue.I have plenty of experience in designing computers, and I can get you a major bang for your buck. Building computers are like lego. It's just a bunch of slots you need to put in. There isn't soldering, no tricky configuration, and if your careful, nothing to go wrong. I currently run a box (Not designed to be a bang for your buck, rather a future proofed machine) with an i7-4790k (Current i7 bang for your buck spot) GTX 970, 16GB of some DDR3 RAM I had for a few years, and a 500GB SSD.If you feel to go on your own, check out some of the older Xeons. You can get a 4 core hyperthreaded Xeon (Older architecture) for (Refurb) 30$http://www.newegg.com/Product/Product.aspx?Item=9SIA4GH48R9677And if your REALLY in a money pinch, check out Scrapyard Wars from Linus Tech Tips on youtube. They normally have a budget cap, so they use different skills to get the biggest bang for their buck.Again, I am here to help pick out parts, I don't ask anything, happy to help you.

author: wraper
author_rank: Unknown
timestamp: September 18, 2016, 05:40:13 pm
content: Quote from: TwoOfFive on September 18, 2016, 05:25:40 pmExperience in both, including expierience repairing failed PSUs. 4 years is about the average when "average" (not the cheapest stuff) PSUs start to fail with bulged capacitors. What most of all suggests about fail of the PSU is need to disconnect it from Mains.

author: Ampera
author_rank: Super Contributor
timestamp: September 18, 2016, 05:49:05 pm
content: Quote from: wraper on September 18, 2016, 05:40:13 pmI have a build from the Athlon XP era. I still use it as a music room system.

author: wraper
author_rank: Unknown
timestamp: September 18, 2016, 05:58:51 pm
content: Quote from: TwoOfFive on September 18, 2016, 05:49:05 pmThen PSU is either of good quality with Japanese capacitors used, has low load for it's power rating, or was not used that much. On the other hand, motherboards from i-7 2600 time period, nearly never develop capacitor defect (unlike those from early-mid 2000s), and many don't use or use a very limited amount of them.

author: Ampera
author_rank: Super Contributor
timestamp: September 18, 2016, 06:09:16 pm
content: Quote from: wraper on September 18, 2016, 05:58:51 pmI actually have a modern PSU in it. It's only a ATX-20 connector on the board (Why they needed another 4 I will never know unless I look it up, but who has time for that.) so the PSU I am using is a bit overkill, but the one I had in there (A Cheifmax one I think, I forget) I modernized with newer connectors, and thus was suited more for a SATA based system than a PATA based one.

author: Bud
author_rank: Super Contributor
timestamp: September 18, 2016, 06:24:42 pm
content: I had that nvidia driver error on my GTX460, it was the GPU failing, fixed it by disassembling the graphics card, heating the GPU to 120C for 10 min, then reapplied the thermal paste.https://www.eevblog.com/forum/repair/my-experiences-reflowing-videocards-(so-far-100-success-rate)/msg874097/#msg874097

author: wraper
author_rank: Unknown
timestamp: September 18, 2016, 06:25:59 pm
content: Quote from: TwoOfFive on September 18, 2016, 06:09:16 pmBecause of increased power consumption of modern PCs. Additional wire for each power rail.

author: sony mavica
author_rank: Frequent Contributor
timestamp: September 19, 2016, 02:20:20 am
content: Quote from: Monkeh on September 18, 2016, 03:01:45 pmyes it was the push pin

author: sony mavica
author_rank: Frequent Contributor
timestamp: September 19, 2016, 05:40:26 am
content: my friend found a push pin in his draw so he gave it to me so i have fixed that nowalso one other problem is that the cpu has very little thermal paste anybody know what paste i would need for italso the power supply seems to work fine after i opened it up and got rid of the rest of the dust inside it but i still will try and replace it asap

author: Brumby
author_rank: Unknown
timestamp: September 19, 2016, 09:20:51 am
content: The subject of thermal paste is one that has raised many "deep and meaningful" discussions.Last I went looking I was after some Arctic Silver (there are several varieties) - but that wasn't available from the place I went to, and I walked out with some Noctua NT-H1.Either of those are good, IMHO, but there will be some who might want to be more 'particular'.Don't go for the cheap white paste. It will dry up more quickly than you might like.

author: wraper
author_rank: Unknown
timestamp: September 20, 2016, 06:44:59 am
content: Quote from: Brumby on September 19, 2016, 09:20:51 amWhite paste is good enough if not overclocking.

author: Brumby
author_rank: Unknown
timestamp: September 20, 2016, 07:09:58 am
content: Overclocking or not, it will dry out quicker than you might like - or at least quicker than I like.The white stuff will work - but the higher the temperatures and the longer the time, the less effective it becomes. While this is generally true of any thermal compound, the white paste is at the bottom of the list.

author: BradC
author_rank: Super Contributor
timestamp: September 20, 2016, 07:32:36 am
content: Quote from: Brumby on September 19, 2016, 09:20:51 amAS5 & NT-H1, my two favs. Oddly enough last month I had to re-apply AS5 to the CPU in my 2006 vintage Mac Mini. I upgraded it from a Core Duo to Core2Duo back in 2009 and used AS5. It recently started shutting down on overheat and turned out the old AS5 was a bit dry. First and only time I've ever had to re-apply thermal paste.

author: wraper
author_rank: Unknown
timestamp: September 20, 2016, 07:37:17 am
content: White paste on the bottom but because of a big heat spreader on top of desktop CPUs, that is not so critical compared to laptop CPUs and GPUs where you have just a bare silicon die.

author: Brumby
author_rank: Unknown
timestamp: September 20, 2016, 08:19:21 am
content: Yes, laptops do offer a much more significant thermal challenge.I haven't had much work on them - but the only overheating one I was presented with was fixed when I removed the dust blanket that had formed at the air intake. Seriously, it was almost like felt!

author: tautech
author_rank: Super Contributor
timestamp: September 20, 2016, 08:32:34 am
content: Some friends down the road had a PC with similar symptoms, pushes to the power button would result in a "lucky dip" as to whether it would latch on and boot.After a number of "taps" it latched on and a finger "walk-around" the Ecaps on the MB found a few that were f***ing hot....in seconds.Full MB recap and it's still going strong ~2yrs later.

author: wraper
author_rank: Unknown
timestamp: September 20, 2016, 08:45:39 am
content: Quote from: tautech on September 20, 2016, 08:32:34 amNot likely to be the case with more or less recent motherboards, most likely there are polymer capacitors on the CPU power anyway.

author: tautech
author_rank: Super Contributor
timestamp: September 20, 2016, 08:51:41 am
content: Quote from: wraper on September 20, 2016, 08:45:39 amMaybe, but the OP has said ~5 yr old MB. Isn't that getting on a bit ?

author: TerraHertz
author_rank: Super Contributor
timestamp: September 20, 2016, 09:19:35 am
content: I too would suspect the power supply, and want to get onto that right away. Having had PCs destroyed by power supply fails.First thing is to check the rail voltages while running. This is easy, because the motherboard connects GND to the metal case via the metal screw mount points. And the power connector to the motherboard may look like plastic covered wires going into holes in a nylon connector body, but the metal crimp pins are just below the connector top, and can be reached with a pointy probe easily.Do you have a scope or even a multimeter? With a multimeter, stick the common probe tip in some open screw hole on the metal case (ground), and shove the Plus tip down into the holes in the top of the power connector. The plastic walls between pins prevent shorts. Wire colors are fairly standard: red is +5, orange is +3.3, yellow is +12, etc. Anyway you can find the pinouts online.Ideally you should have a look with a scope for ripple too. Or use the multimeter on AC volts.Btw, I've had older motherboards exhibit unreliable boot (or no boot at all) when the CMOS RAM coin cell is nearly flat. It should be at least 3V. You can measure this relative to the chassis too (with the machine off.) Don't short circuit it, as you'd lose the CMOS setup.

author: wraper
author_rank: Unknown
timestamp: September 20, 2016, 10:11:12 am
content: Quote from: tautech on September 20, 2016, 08:51:41 am5 years ago most mobos had poly caps already. Even my motherboards from 2009 have them.

author: rdl
author_rank: Super Contributor
timestamp: September 20, 2016, 02:17:04 pm
content: Quote from: wilfred on September 20, 2016, 09:59:49 amYesterday I added a drive to this computer (actually just an eSATA port). It hadn't been opened in years and the dust inside was horrible. What's worse, I must not have cleaned the power supply last time. It may not have been cleaned at all in eight years. It was so choked with dust and fuzz I can't believe it was still working. I had to disassemble it to get all the gunk out.Got it all put back together and everything is working fine. Eight year old Gigabyte motherboard and Seasonic power supply with all caps looking like new.