A very odd laptop issue. intermittent power problems

[Mezmer32]

Hi,
I've been fixing laptops for years but my own has me stumped. So before i start replacing stuff i'd like to know a few good places to start. the laptop has a few issues which could be important, its time for an upgrade anyway but i need it for at least another 3 months.
So heres the details and sequence of events.
the laptop is a 3 year old dell xps17 L701
1st gen intel i7 740QM
nvidia 445M GT
8Gb ram

1. Batterys been caput for about a year, it still works but only about 15 mins on full charge.
2. The hard drives showing signs of tiredness, the occasional blue screen (quite rare) and explorer slows when copying multiple files seperately, but it still runs the latest games as smooth as i could hope for.
3. about 4 or 5 months ago the laptop booted up but made loud high pitched beeps, in threes with about 3 seconds pause in between, but the laptop seemed to function normally but the beeping wouldnt stop, and it was fine after a reboot, it does this occasionally like maybe once a week .
3. about a month ago the real problems began, when you press the power button, as far as i can tell theres about a 1 in 20 probability that it will power up and function normally. otherwise what happens is the power button lights up like it would but goes of quickly, and at the same time you can hear the hard drive make a brief noise like its reading and then its dead. the noise and the flash both last prob 1/4 of a second.

so sometimes i press the button and it comes on first time, sometimes its 2 or 3 presses, but quite often im sitting pressing it 20 or 30 times and it eventually comes to life and acts like nothings wrong!!!
4. as of yesterday its begun randomly going to sleep, it seems to do it a lot if im watching a video online, like 3 or 4 times during a 40 minute show and it nearly always comes back on first press of the button, but its not normally as easy as that if i click sleep from the taskbar. if im playing a game it might do it once or twice in 6 hours.

and if i just leave it, it will randomly just come back on...sometimes. i first noticed it before it ever went to sleep on its own, it turned on randomly.


i think the sleep thing could be a spyware problem, i use eset internet security. also my power cable is quite loose however it always says plugged in and charging and the laptop is always parked on a shelf and i use a wired keyboard and mouse and tv.

id appreciate any advice

-Simon

 

[mc962]

For number 3, was it a beep like a beep code from a motherboard speaker? I did a quick google search for beep codes and, assuming I found the right manual (ftp/ftp.dell.com/Manuals/all-products/esuprt_laptop/esuprt_xps_laptop/xps-17_setup%20guide_en-us.pdf), not sure if it's the right one, but if it is then the 3 beeps, according to the manual, indicated "Possible system board failure — Chipset error"
Maybe you might be able to help it by reinstalling the chipset driver, although there could certainly be worse issues that a driver wouldnt fix

 

[Mezmer32]

hi, yes its a definite system beep, it starts before the dell splash screen shows up and i cant lower the volume etc. I didnt notice any difference in performance. You think maybe the cpu is done? I thought of that, but thought it couldnt be if it runs completely fine even while it beeps, im gonna look at that manual now. I thought maybe heat was causing the random sleeps for a while but it gets a hell of a lot hotter during games than watching videos. core temp showed 61 celcius during a video, and it cant be the gpu if gaming doesnt make it worse.

Update....Just ran the intel cpu diagnostic tool and it passed everything.

 

[mc962]

From what I understood the code said that there was an issue with the board, not the cpu

 

[Mezmer32]

yea i was afraid of that, its about £100 for a new board. Do you think thats whats causing the weird power button behavior?

 

[mc962]

I could see that being a cause. You might want to test a working battery just to rule out everything, but if the board is on its way out then everything else is likely to have issues..the computer seems to think so at least

 

[Mezmer32]

I FIXED IT!!!!! FOR FREEEEEE!!!!

The problem got worse and worse...
So i dealt with it a while longer until it started randomly going to sleep a LOT! sometimes i could play a game for 2 hours and sometimes it would give me 30 seconds inbetween 2 or 3 consecutive restarts. Also for the last 2 weeks the sound through the hdmi from the laptop to the TV has been jumpy, like a second of normal sound then 1 or 2 seconds of silence.

SOLUTION BIT
So after trying a different hard drive it with a fresh install of windows which had no effect i took it apart, in fact i only had to remove the cdrom, and 7 screws to pop the keyboard and surround off and noticed that the red and black power cables from the subwoofer had worked loose from the tiny socket and was sort of dangling against the pins. So obviously one thing at a time so i know what fixed it, I put it back in, put the top back together and pressed the power button staccato (gently and very briefly) and it worked first time. Recently the record has been 15 seconds holding in that button before it randomly comes to life.
So anyway its been on for 72 hours give or take a few planned restarts while installing stuff and has booted up first time every time and the sound works through hdmi and it hasnt turned itself off once, or beeped or anything.

Anyone wanna buy a laptop? £450