Computer Problem

[jollytiddlywink]

I have a problem with my laptop. Several times recently, it has instantly shut down without warning. No blue screen, no error message, it just dies--screen goes dark, CPU stops. When I turn it on again, it boots normally, as if nothing was wrong. It only dies like this when it is both
1: plugged in and charging
2: running a game (thus using most of the CPU capacity)
It does not do this if it is charging but using only a little CPU capacity (for example, running firefox and word) or if I am playing a game but using only battery power. The laptop itself was bought in late 2004. It had the hard-drive replaced 8 months ago, but (with the exception of needing a new hard-drive) has not had any other problems.

Naturally, this is only really a serious impediment if I want to do a lot of gaming, at least right now. But computer problems always make me nervous in case they get worse.
Any idea what this might be, or what I could do about it? The IT helpdesk is the obvious place to go, but I'm a bit short of cash at the moment, and getting it diagnosed there runs to 25 quid, if I recall correctly from last year. Thus I trust to the Sinner for help.

[Timata]

Is it possible it might be overheating? Mine does that if I use a lot of the CPU and don't balance it on something to keep the fans clear.

[jollytiddlywink]

Its possible, but unlikely, I think. I have it slightly elevated off the desk, so the fan is perfectly clear and gets plenty of airflow. In any case, it usually 'goes' within a few minutes of the power cord being plugged in, and I haven't noticed it being any warmer than it has often been in the past, in fact its probably cooler.

[Fawksie]

When it's not plugged in, it will throttle the CPU to save power. When it is plugged in, it will run it at full capacity. The thermal junction between the CPU surface and the heatsink might have become less efficient than it should be, with the result that the CPU itself is overheating under heavy load, without the rest of the laptop getting warm.

Download SpeedFan, set it to graph the CPU temperature and run your game for a couple of minutes. Post the top temperature here and we can tell if it's in the right ballpark. If it's getting as high as 80 - 100 degrees Celsius, then the heatsink will need to be removed from the board (or vice versa) and reinstalled.

[jollytiddlywink]

I've used SpeedFan. First I played the game on battery power. It went from a background temp of 52C, up to 62C when I started the game, and then stayed there for the next 15 minutes of gameplay. I plugged the laptop in, and the chart went shooting up, it took about 30 seconds to hit 75C. That seemed quite high enough, so I quit the game. The chart immediately fell again, and leveled off at the original 52C. Then I plugged in to charge again and the temp went up to 55C. So it seems you're right, Fawksie. I suppose now the only question is finding the cheapest place to fix the heatsink problem.

[another unreg]

If you have any luck finding a place to get it fixed for cheap in St Andrews then if you could say where you managed it that'd be great. I've been having the same problem as you for a while now but have (somewhat stupidly, I suspect) put off doing anything about it or bothering to try and fix it myself.

[Fawksie]

Yeah, sounds like what I expected. Rapid changes in temperature when load is applied and removed generally indicate bad heatsink contact. My own laptop does the same thing thanks to Apple not knowing how to apply thermal compound. I'll need to wait until I have a backlight inverter on hand though, and install that at the same time as reseating the heatsink. Managed to smash it to bits by dropping the laptop on the doorstep...

[2jays]

What CPU does your laptop have? Mine is a SI-40 Sempro and they run hot normally (75 to 85 degrees normally, peaks at 92!). Pretty shit as it makes the laptop too hot to put on your lap. Also if I leave it on my bed for 20 minutes covering over the vents the laptop will shut down from overheating. If your laptop is new to expressing similar behavior to this, unlike mine which has always done then yes it could well be possible that you need to check your cooling checked out.