Laptop dying at random.

March 1, 2005 10:14 AM

I've got a Compaq laptop (Presario 735 US) that's lately started to die on me, almost at random.

The laptop is about three years old and well out of warranty. When it dies, the screen blanks out and all activity stops, but the power light stays on. The laptop's plugged in to the wall, so it's not the battery going flat.

When it dies, it won't come back on immediately; pressing the power button makes the power light come on, but nothing else happens. The light stays on until the laptop is unplugged from the wall or I press and hold the power button. It will usually come back to life, but only after I let it sit for a while.

It seems to happen most often when the processor fan kicks in, so I'm thinking that there might be a problem with the power supply. What might be causing this? Can I do anything to fix it, or should I just replace it?

posted by staresbynight to computers & internet (6 comments total)

Sounds like it's overheating and the system automatically shuts down. Check the fan is actually working, and that the vents are clear of dust. Sit the machine on a table, rather than a lap (if that's the case).

Get yourself something like SiSoft Sandra, or MotherBoardMonitor to check the temperatures of the CPU.
posted by benzo8 at 10:23 AM on March 1, 2005

Well... my guess is that something might be up with your BIOS and ACPI settings. What I would do is make sure that you have the lasted BIOS revision installed on your computer.

Other than that something might be overheating (I.E. processor gets too hot so the BIOS shuts down the system)

That or you may have an intermittent power supply or the fan is going out.

Trial and Error is the tactic I would use. If it's not any of the above; look into the power settings in your op sys. If it's windows, I suggest doing a back up and reloading. Also there's lots of test software out on the web, check out Gold Memory Tester; maybe it's a bad memory thing.

But I am only stabbing in the dark here though :-)
posted by Livewire Confusion at 10:39 AM on March 1, 2005

Could be overheating that is causing the shutdown. Do you have a way to monitor that? What is a safe laptop operating temp anyway? Mine idles at 51 C, but will shoot up to 61-62 when it is thinking. I have no idea if it is safe or not, but it should give you a benchmark.

Try this...

Take the battery out and run with the adaptor only. See if the problem goes away. Could be you have a bad battery and it is causing a problem even though you are plugged in.

Luck!
posted by achmorrison at 11:49 AM on March 1, 2005

achmorrison: when the problem first occurred, I took the battery out and that seemed to do the trick. (It's a flat old battery anyway and doesn't keep a charge.) This worked for about a month or so, but now the problem's recurred.

I was hesitant to ascribe it to overheating, but it's possible that this is happening; I keep my hotel rooms frosty and it doesn't seem to happen so much then.
posted by staresbynight at 12:04 PM on March 1, 2005

benzo8: SiSoft says that the board temperature is 175° C (!), but also reports that fan speed is constant even though I can hear it speeding up and slowing down, so I'm a little less than confident about it.

MotherBoardMonitor doesn't seem to detect anything, even with the appropriate motherboard selected. However, you've given me a good starting point and I'm going to have to look at this more from a ventilation and heating perspective than a power supply one. Thanks!
posted by staresbynight at 12:44 PM on March 1, 2005

My dad has a an older compaq and it has started to do the same thing.
Im pretty sure its due to heat because if you feel one particular part of the casing, it seems to be much hotter then it should be.
posted by Iax at 2:15 PM on March 1, 2005