random shut down

Gateway Laptop MD7818U specs on it
vista
intel core2 duo processor T6400 2 MB L2 cache 2GHz 800MHz FSB
4 GB DDR2 500 GB It powers down, power cord tests good, battery is in but won't hold much of a charge. Fan was cleaned, nothing there to report.Fan does work at power up then stops, sounds like it always has quite.Did look at power button, looks okay. It now won't stay on long enough to do anything. I read old posts on this but never really fits my situation. Look forward too your help and ideas.

Does it boot all the way into Windows then shut down?
How long is it on?
I know you checked the fan and cleaned it but does that area get hot while it's on?
or does it not get thru Post? IE the Gateway Screen

It will load windows and shut down, other times it will not, all different. The last few starts hard to check if it gets hot, won't stay on long enough.I have put a fan blowing cool air, still would shut down.

I've a few ideas.
Does it Blue screen and reboot...at boot up tap F8 repeatedly to get to Advanced options screen and click on Disable auto restart on system failure to see if you get a BSOD.
If not
Does it act the same in safe mode?

As I recall Gateway has a diagnostic partition.
I think press F12 or F10 should see it at bottom of gateway screen.
Get to diagnostic screen and run all the diagnostics.

It sounds like a imminent hard drive or Motherboard failure

I've a few ideas.
Does it Blue screen and reboot...at boot up tap F8 repeatedly to get to Advanced options screen and click on Disable auto restart on system failure to see if you get a BSOD.
If not
Does it act the same in safe mode?

As I recall Gateway has a diagnostic partition.
I think press F12 or F10 should see it at bottom of gateway screen.
Get to diagnostic screen and run all the diagnostics.

It sounds like a imminent hard drive or Motherboard failure

No blue screen. It will do the samething in safe mode. I have tried to do diagnostic, will shut down during it.I just plugged in the power cord, battery in, hit power button. os did load, then after a minute, OFF. Did notice the power light of course goes out. Did not touch anything and no lights would light up. I then moved the power plug some and the light did light up. will power up and repeat. I did test power cord, but don't have a spare to try.

Does it Pass POST. Do you hear One beep (normal) or many beeps

Try to eliminate the battery Please remove the battery from your laptop and go on AC power and try to boot it.

If boot is successful, Please let it sit for five or 10 min if it shut down less than that amount please let us know.

if after a hour or two you notices that its normal then you have a battery issue

I agree with Coxchris. If it still does the same thing without the battery you really need to test with another power adapter before proceeding. You may need to get creative why not just call a local repair shop to see if they will look at your laptop and test the power adapter. I'd do a free diagnostic to sell you an adapter.

Does it Pass POST. Do you hear One beep (normal) or many beeps

Try to eliminate the battery Please remove the battery from your laptop and go on AC power and try to boot it.

If boot is successful, Please let it sit for five or 10 min if it shut down less than that amount please let us know.

if after a hour or two you notices that its normal then you have a battery issue

It won't work with out the battery installed, I will go to a repair shop asap. Will be out of town but will keep you informed. Thanks big time for the input.

Will with a new power cord it seemed to stay on a long time, then its like it switched to battery mode (which battery won't hold a charge) then shuts down. After a few seconds the light comes on (tell you that the power cord is plugged in)and will power up. Why it would stay on longer ?? its 90 out here today in MI.

Do you know how to enter BIOS Setup?
If yes, please go to BIOS Setup and go to sleep for a couple and see does your laptop shutdown or it will still on

If it's shutdown, turn on your laptop and go to BIOS Setup and find Hardware Monitor or something like that and watch your Processor Temperature, if it have autoshutdown function please disable it as your Mainboard have that too so leave it to Mainboard to take care not your BIOS

If in BIOS that autoshutdown set at 60⁰ C then BIOS will shut down your laptop if your Processor reach 60⁰ C, so please disable it and try to use your laptop in heavy use does your Laptop still get shutdown or not

Do you know how to enter BIOS Setup?
If yes, please go to BIOS Setup and go to sleep for a couple and see does your laptop shutdown or it will still on

If it's shutdown, turn on your laptop and go to BIOS Setup and find Hardware Monitor or something like that and watch your Processor Temperature, if it have autoshutdown function please disable it as your Mainboard have that too so leave it to Mainboard to take care not your BIOS

If in BIOS that autoshutdown set at 60⁰ C then BIOS will shut down your laptop if your Processor reach 60⁰ C, so please disable it and try to use your laptop in heavy use does your Laptop still get shutdown or not

I tried to but it shut down right away. But not familiar with bios and may have not did things correct. Tried again and it did a memory test and stayed on threw the whole test. It restarted, did f2 and has been on for some time now.

Could you touch your Laptop and feel does it some heat or not?

Was able to get into bios, it did shut down. Did not feel that warm to me.

I have four things in mind, one or more which might be happening:

1. BIOS may have gone corrupt
I recommend to upgrade your BIOS

2. RAM Problem
Check with different sticks to see if it remains on.

3. Hard Drive
Try listening to the sound of the hard drive when it shuts down. If it screeches and shuts down, there may be a problem.

4. Overheating
If your computer shuts down and before the next run it has to be cooled down, then you have overheating. Either some fan is not working or your computer does not have proper ventilation.

When I had this problem, the BIOS had become corrupt due to voltage fluctuations. My solution was to get a new power supply and a BIOS upgrade.

I have four things in mind, one or more which might be happening:

1. BIOS may have gone corrupt
I recommend to upgrade your BIOS

2. RAM Problem
Check with different sticks to see if it remains on.

3. Hard Drive
Try listening to the sound of the hard drive when it shuts down. If it screeches and shuts down, there may be a problem.

4. Overheating
If your computer shuts down and before the next run it has to be cooled down, then you have overheating. Either some fan is not working or your computer does not have proper ventilation.

When I had this problem, the BIOS had become corrupt due to voltage fluctuations. My solution was to get a new power supply and a BIOS upgrade.

Great, I will look into this asap and post back, Thanks