Power Pulsing (among other problems)

[DrRiverSong]

Hi,

Sorry for the long post, but please hang with me here. I am way out of my depth and will be very grateful for any help you can give me.

A few months ago i bought a custom built computer. Very good condition had been kept clean and well looked after by the guy who built it. Had run perfectly for him - he never experienced any issues with it. Here are the specs as listed by the guy who built it:

CPU: Intel i5 3570k - Not Overclocked but very capable of 4.5Ghz
RAM: 2 x 4GB Corsair vengance DDR3 1600mhz
GPU: Sapphire AMD 7870GHZ Edition
Motherboard: Asus Sabertooth Z77
Harddrive: 1TB Seagate Barracuda
SSD: Samsung 830 Seriers 128GB
Power Supply: Silverstone STF750W
Case: Coolermaster HAF912 Advanced w/ window
Includes Windows 8.1 Pro Installed
Cooling:
Fully custom XSPC watercooling kit worth: $150
Keeping the CPU around 22 Degrees 24/7

The computer ran perfectly the first few days after I bought it then every few hours it started freezing. It froze regardless of what i was doing at the time and the only way to get out of it was to force power off. It started doing this more frequently, every hour or so. It then forgot how to boot up by itself, i had to select the correct boot from the BIOS settings (which I only figured out how to do through trial and error). At this point i started looking online for suggestions. Someone recommended that the drivers could be out of date, so I installed SlimDrivers and updated them all. This worked for a day or so, but the then the computer started freezing again, getting more and more frequent.

It started completely crashing as well as freezing. At some point it started booting up on its own again without me messing around in BIOS. Soon though it couldn't even finish booting up before it crashed again. If i left it alone for a few days it would run fine for a hour or two before spiralling into freezing/crashing again.

After leaving it alone for a few weeks i took it into a computer repair place who ran some diagnostics over the course of a couple of days and found nothing wrong with it at all. I believe it never crashed or froze when they had it. They told me it could be a problem with the power supply at my house. I took it home and plugged it in in another room. it worked fine for four days and then started freezing/crashing again.

Now when I turn it on, it powers up for about two seconds, then dies, then powers up then dies again. It just continually pulses like that and i cant turn it off or stop until i pull the plug at the wall. Its not dirty or dusty inside. From what i could tell before it started power pulsing and not turning on, the internal temp was running around 20-30 degrees.

I have no idea whats wrong with it, i don't want to take it in to the shop again because they charged me $100 for them to not fix it last time and i cant afford to keep throwing money at them with no results. I don't know computers well at all so please keep that in mind if you reply.

Again, I will be very thankful for any help you can offer. I am at the end of my rope with this thing.

Thanks.

[fandtm666]

1: unplug it from power point

2: remove side panel

3: take everything out except cpu and cpu fan

4: plug in one stick of ram and turn unit on

if it boots into the bios then turn power of and install the hdd and
turn power on if it then boots into your os then let it run for a while

now its a matter of trying one piece of hardware at a time to see what was
the problem , but from what you have mentioned i feel it is either a faulty stick
of ram or even a faulty cpu fan

[DrRiverSong]

okay thanks, i will try that. Is there anything important i should know before i start pulling my computer apart?

[Philquad]

forget the cpu fan, its water cooled
i would, unplug it, remove cmos battery & move jumper to cmos clear position (or however for that board) 24 hrs (wipes bios)
battery back, cmos back, 1 stick ram, doubt that mb has onboard vga so card too
boot to bios > stable? > yes > hdd ect, next
stable no> maybe cpu, ram or mb board > sadly, probably board
they do that, but $60 gets a new basic job
look on board for bulging caps
i had a new 1 the other week (6 months old) i thought fan ,no, psu, no, ram, no, was the board

[Philquad]

before you do anything
go into that bios & set default settings
maybe its on oc settings

[I]n english, turn it on, hit delete key, bios, does it stay running?

[DrRiverSong]

thanks for the translation

I cant check that because of the weird pulsing thing it does when i turn it on. its only on for about one or two seconds before it turns off again, so it never gets far enough to go into BIOS.

i am trying to do what you said earlier about the CMOS, and i have found the jumper and figured out how to change it to clear, but i cant find the CMOS battery on this motherboard (Sabertooth Z77 i think).

[Philquad]

rip the plastic off

[gordonwh40]

Why not start simply and ask the previous owner about the problem before pulling the computer apart? Here is an qwner obviously struggling and all he gets is very technical suggestions. Remember KISS

[lsemmens]

I'll chuck my 2c into the ring. I'm suspicious of RAM (memory stick). I resurrect ex govt computers for those who are less fortunate than ourselves and often find that If the RAM is not suited to the MOBO some machines will display those symptoms. My first test is usually to, as already suggested, unplug everything except one stick of RAM and then start swapping sticks around until I find a stable one (I have quite a collection). Once found, I then start adding components back.

Of course you might have a software issue, but, given the symptoms, I doubt it.

[DrRiverSong]

So far i have tried switching around the RAM sticks, putting them in one at a time and things, this had no effect. I am too afraid to take everything apart and just run it with just the CPU and RAM because i feel sure i will accidentally break something or do something horrible to it. Im also afraid i will get it all apart and not know how to get it all back together.

Moving on to the second suggestion, i have tried resetting the BIOS by switching the CMOS jumper to clear and keeping it there for a while then putting it back to normal again. No effect. I tried moving the jumper to clear and left it there overnight and the next day, then putting it back again. No Effect. I have tried to find the CMOS battery but best i can figure is it is beneath the thermal armour. I tried to remove the armour but after removing what i think is the graphics card (a nerve-wracking experience) and all the screws that seem to attach the armour to the motherboard, it still wouldn't budge. I don't know if it is attached some other way as well.

Third suggestion - i have already asked the previous owner (who is also the guy who built it) if he had any problems and he said he had never experienced anything wrong with it. He seemed like an honest guy, but who knows.

fourth suggestion - Im too afraid to pull it apart and nothing i did with the RAM sticks made any difference (i tried putting them in one at a time and in different configurations) and i am afraid i dont have the RAM stick collection you have so i didn't really have anything else to try.

Looking around more online i found a guy who had had a similar problem as i do and his turned out to be something wrong with the CPU. What i think is my CPU though, is covered/underneath part of the RayStorm water-cooling kit and thus effectively inaccessible to someone with my lack of knowledge. It is possible it could be the CPU in mine as well? should i be looking further into doing something with the CPU?

Thanks for all your help so far guys! please keep the suggestions coming.

[lsemmens]

Actually, there is nothing much you can break by unplugging the drives and the various cards, as long as you are careful, it isn't too hard. Just take your time and, if you are uncertain, take a photo before you pull it out. The motherboard mfg's website will have instructions for board layout and what plugs into where. They should also have instructions for replacing the CMOS battery which is most likely a CR2032 (a $2 item). We are also here to provide some help too. Whereabouts are you? One of us may be close enough to assist you if you run into strife.

[Bibliophile]

Is it possible that the water cooling system is not working correctly causing the CPU to overheat and shut down?
My son fried a CPU on his water cooled rig because he didn't put an anti algal agent in the system and it blocked up.

[Uncle Fester]

Strange hat nobody mentioned the power supply (PSU).

Would be fantastic if you had another computer to take it out and swap it.

However it may be simpler to first take out the graphic card and run it from the onboard graphic.

If it then works then you have narrowed it down to the PSU or Graphic card.
Then swap the PSU or try the graphic card in the other computer and you should know the culprit.


BTW I have been "messing" around with computers for over 30 years and I can not remember ever having a faulty CPU(well not on a IBM compatible type PC), although I often falsely suspected it. So don't play around with the cooling on that if it is very sophisticated. That is the last place I would look. Also they don't overheat in a few seconds.

The most common failures I have are GPU related, dodgy PSU and RAM

[Philquad]

it wont have a gpu card
its a high end game job

yes he needs spares, psu = deffo
i was guessing maybe its in oc mode, too much
i had all this same drama with a intel lately, didnt get it right until we took cpu out, then tested again, it was the bios all along
also the water cooling, really need a stock fan to test it with 1st before the water job. umm

[Philquad]

looks tricky,
page 27, shows battery

im so nice, send me the board & cpu, & ill send back the cpu running on a new board for free
(joking)

oh, its a 1155 socket, there old now, did you buy it from ocau?
seems that board has 5 yr warranty,

[Uncle Fester]

Still be a lot easier to try with another more low power graphic card if available

[Philquad]

sorry if im wrong

but wheres the onboard output?

the hdmi? i never new that, i thought they needed the standard type plug

[Uncle Fester]

Yes I was a bit confused because I read on that site about GPU support but they only mean crossfire for two external cards.

Still insist that it is not an overheating issue if it shuts down after only 3 seconds while only trying to boot up (unless it is still hot from running for a longer time before).

Initially working but freezing then getting worse and eventually failing after a few seconds could very well be some CAP inside the PSU progressively loosing it's value

[DrRiverSong]

#11: thanks for the vote of confidence i might try pulling it apart after all, but i would want to check out my other options first, see if i can avoid messing around with its innards too much. its probably un avoidable at this point though... the photos are a great idea and i will defiantly do that if i resort to disembowelling it. i doubt anyone lives close enough to help, i live near Boonah (the middle of nowhere), but its a nice thought anyway.

#12: i dont think it has time to overheat before shutting down (it usually pulses around 2 seconds on, five or six seconds off) but is it possible that it overheated before it started pulsing and i have already totally fried the cpu? there is one part of the water tubing that is a bit kinked, not enough to completely stop water flowing, but it could be enough to slow it down, could this contribute?

#13: i tried pulling out the graphics card and turning it on - no change, still pulsing.

#15: i dont know what ocau is, but i didn't built the computer, the guy i bought it from did. i can ask him if its important.

#16: i tried it without the graphics card in at all and it didnt work, i dont have another graphics card available

I just took another look at the tubing in the watercooling system and the kink is much worse than i remember it being, i think it is completely blocking water flow. any tips on how to fix this? and could this have totaly fried the CPU? i found it surprising that this is completely kinked, because when the computer shop had it, they had it running for hours on end and were monitoring the temp so i dont think it overheated at all when they had it. could this be the problem? would it be able to tell that the water is not flowing and automatically shut down?

thanks

[dai]

sounds like the psu

i had a silverstone psu once it decided to crap out and left an extensive damage trail throughout the house costing thousands to repair

look at seeing if you can borrow a 80+ quality 750w or better to try in it

quality units come with at least a 5 yr warranty

corsair hx.tx.ax models
seasonic
thermaltake toughpower model