Hi
My notebook turns itself off, after some time...seems to be random periods.
Sometimes it can't be turned on again for several hours.
Sometimes it can be turned on - under battery power but not AC.
The battery is probably close to the end too... doesn't seem to keep much charge.
Yesterday the notebook asked for new time and date settings on startup.

Thought it could be overheating and have installed c diefer's fan control software - http://www.diefer.de/i8kfan - the fans work, but the cpu temp gets up to about 65 C if I run several programs at once - is that too hot?
Have also read about dust buildup being a problem & attempted to blow out any dust - didn't notice much dust coming out.
Any help would be great
Thanks
Kazim C

Hi,
Is the Inspiron 4150 a Pentium or an AMD based system? 65C sounds ok for an Athlon, bit hot for a Pentium though.
It could be turning itself off on purpose...some motherboards come with sensors and software which when activated, monitor the temperature of the motherboard and CPU and will turn the PC off when it hits its maximum permitted temperature (probably variable). It will not let you turn it back on until its returned to a reasonable or set temperature.
First I would check your motherboard manual for more information on this (consult the manufactures website if you don't have the manual).
Unfortunatly I don't know enough about laptop batteries to comment on your other description but the last time I had to remind a PC what the time and date was the CMOS battery was about to die. The CMOS is the little chip that reminds your PC when you turn it on that it is indeed a PC, and not a carrot for example. It's battery may need replacing.
Really could use a laptop expert on this one though...

Thanks Gabriel. Its a Pentium 4. I'll try to find the motherboard manual.

Yes Gabriel, you're right - laptops also have internal batteries that remember the settings such as date / time, hard disk type, boot device order, the fact they are laptops and not carrots, etc

The 4150 is a modern machine though - would be pretty bad luck to have a dead CMOS battery already. But that does sound like what's happened.

If it can be turned on with the battery but not the power supply, that suggests to me that there might also be an intermittent problem either with the power supply itself or the internal connections that the power supply plugs into - I've had that problem with a laptop before and had to send it in to be repaired. Incidentally, if the PSU is going a bit doolally, it might be over-powering the system, resulting in excessive heat build-up.

If it is, a quick call to Dell support might be more productive as this may be a known issue on those Inspirons. They're quite helpful despite the call centre now being in India (AAAAAAARRRRGGGHHH - DJNafey tears his hair out as another one of his suppliers makes all their British/Irish support experts redundant). If it's still in warranty, you shouldn't be charged for the support call or any repair / replacement PSU that might be necessary.

Thanks DJNafey - machine has remembered the date & time for a couple of days now. It there is an intermittent power problem could the CMOS battery have been temporarily low? Another thing I noticed with the fan control software I installed is that the CPU speed under battery power is 1.2 MHz compared with 1.7 Mhz with AC power. Is that normal? The battery is rated 15V while the power supply is 20V.
Kazim C

Not too sure about the voltage difference but the speed difference under battery power is definitely normal. Laptop CPUs often slow down to use less power, thus conserving your battery power so that it lasts longer. If you'd prefer it not to do that, go into the Power options in Control Panel. If you've got a little green flag icon in your system tray down at the bottom of the screen next to the clock, you can also double-click that to get directly to the speed settings.

I don't think that an intermittent mains power problem would cause the CMOS battery to fail. CMOS batteries last years and years normally so it might be that they get charged up a little bit by the power source for the laptop. However, if you were running the laptop off of the battery pack, then the battery pack would certainly have run out of juice before the little CMOS battery, at which point the laptop would have switched off and the CMOS battery should have kept things 'ticking over' for months and months without any problems.