dell inspiron 1150 no post with ac adapter

Just tried removing the battery and running on ac adapter only. good idea but no change. was able to go into safe mode and did a system restore with no change. am currently running checkdisk off my xp disk, again this only works on battery. don't expect to see any change tho, how could a defective windows install(software issue) affect the laptops ability to post? suspect a bios or m/b problem. can't figure out how to reset bios to factory settings. option isn't available anywhere that i can find. it is a dell with the type of bios that had 6 pages which you scroll thru using alt + p. when i go to save and exit there is no option for default settings, nor is there an option on any of the 6 pages. there must be a way to do it, any body out there know what it is?
In answer to NaturaTek: yes it will post on battery only, will not post with know good adapter plugged in, doesn't matter if the battery is installed or not, if the ac adapter is plugged in all I get is the flashing cursor. fans and leds are working properly and if there is a disk in the optical drive i can hear it spin. i am currently running checkdisk, hoping that it has enough battery to finish. thanks for the help

Take a look here
http://www.ocforums.com/showthread.php?t=458369
(forget the one comment of a virus, thats bs and has nothing to do with ac adapter)
Googling dell 1150 flashing cursor, turned up many results, same experiences..usually down to a faulty motherboard and in some cases a faulty drive.

See if you can remove the hard drive, and plug in the power adapter see if you can post at least.

Here's your service manual for your computer if needed
http://support.dell.com/support/edocs/systems/ins1150/sm/index.htm

Check out the 5th comment here:
http://www.technologyquestions.com/technology/mobile-pc-hardware/37334-dell-inspiron-1150-wont-power-psu-working.html

ok, no more posts for a bit, before I get punished.

couldn't finish checkdisk, ran out of battery but i pulled the hard drive and the symptoms are the same. I am back in the bios looking for power settings as jmarti suggests and the only setting is the speedstep which enables the processor to work in different modes. no other power settings and sitll can't find a way to reset to factory default. page 4 of the bios is a power meter showing battery strength and with the adapter unplugged it correctly shows none. when i plug in the adapter i can still manuever in the bios and it is correctly seen as a 90 watt. However if i am running in safe mode on battery only and plug in the adapter, it immediately freezes. Bout the only thing left for me to try is to reset the bios but i'm not getting an answer as to how to do this. I'm about ready to call this one a bad M/B. Any other thoughts out there?

okay, making some progress. after i disabled speedstep in the bios the computer will now post with the ac adapter. but it freezes trying to load windows. went into safe mode, command, checkdisk. rebooted to run and system froze. booted from windows cd to run checkdisk but it doesn't see any windows install, just the partitiion.  so to sum it up, i have moved past the hardware post issue and now am working on a windows problem. when booting off the cd i cannot run repair or recovery as it does not see a windows install.
good call jmarti on the power settings. don't know why disabling speedstep helped but it seemed to get me past the posting problem.

another way is to remove the motherboard battery, but yours is soldered onto the motherboard. :(
Well if you are tech savvy and ready to get dirty, you can unsolder it yourself, remove it for 1/2 hour or so, and put it back in.
Something tells me its the board

http://www.hardwareanalysis.com/content/topic/74120/

If you plug the adapter in and wiggle it, can you feel it firm and you feel the dc jack loose/rattling?

you booting, ok...try hitting f8, safe mode menu and choose 'last known good configuration'
If that doesn't work, start in safe mode and disable/uninstall anything starting up with your pc not needed/recently installed.
Try a repair install last measure

Whatever caused you to zap out before more than likely corrupted your install.

this is making me crazy. in safe mode i installed and updated malwarebytes and it found 20 objects, mostly related to trojan vundo. removed most successfully but needed a reboot, but first then i unchecked all unnecessary tsr's and rebooted. still freezes when trying to load windows in normal mode but now i can't get into safe mode either. it stops at mup.sys.
can i borrow a sledgehammer?
thanks NauraTek but i tried" last known" long time ago and as i previously mentioned i cannot do a repair as when i boot from windows cd it does not see a windows install to repair.
before i run a clean install does anybody have any more thoughts. I have run across vundu many times and while it is pretty nasty i have never seen anything like this!

Sounds like you're corrupted due to infections and who knows what else during the course of your power outage.  If I were you, I'd take out the drive and connect it to a usb sata/ide adapter, connect it to another computer pull out your files, and do a clean install. (if you have anything worth saving)

You can try to go into bios and see if you have a feature ahci/sata/ide. I'll set it sata and try to see if repair install can see the windows. If not, get your hands on a XP cd with sp3 already integrated and reinstall.

I was able to back up files and then reformated and attempted a clean install of windows. now the install freezes at "installing devices" with 35 minutes remaining. Have restarted multiple times and have also tried with a different windows cd. have run memtest which found no problems. I was able to reset the bios to factory setttings and after I did so my original problem returned(system does not post with ac adapter plugged in). So i unplugged the adapter and while running on the battery I again disabled the "speedstep" in the bios. Now i am running off the ac adapter but cannot reinstall windows. i backed up the files by installing the hd in a different computer and the drive seems fine. i'll try testing the drive but i suspect processor or m/b since i have this screwy ac adapter issue. Any more thoughts?