My computer crashed a while ago and it wouldn't reboot. A friend suggested to change the battery on the motherboard, a round one lithium 2032, which I did and was able to reboot but with a message of fan failure. I replaced the fan: (Datech 9232-12HBTL) and was able to reboot and work with the computer for a while. Then I try to watch a movie with Media Player Classic, which came with a K-lite mega pack, and it did not work and sent me to MS Windows web site and they suggested to download a newer version of the Media Player Classic, which I did and then when on Firefox or Explorer they would crash and would not reopen the web and then the dreaded blue screen and the computer shut down and when I tried to reboot it gave only the Bios screen with the F! and F12 choices. After several tries the computer will reboot but will not stay on for long specially going on the web and it'll crash and shut down. Any suggestions

Well... taking a look at the first crash.. as it may be responsible for the other problems. So, why did it crash? Over heating....bad fan or to much dust in the computer. Bad stick of memory. Failing power supply. Fan has been replace..so check for too much dust. Test..run the computer with just one stick of ram at a time. Test power supply: Disconnect any cdroms and second hard drives ....test run. If it is still crashing the files on the hd may be corrupted and it will require a repair install.

I cleaned all the dust and then tried it without the cd dvd roms, worked for a while, even the internet and all and then I tried a registry cleaner and it crashed and shut down again. How do I do the repair install or does it have to be done professionally?

Well you need the installation cd. Then as the means is somewhat lengthy ....but easy google for doing a repair install. Basically ...boot off cd... ignore first repair option use setup to copy files...then bail and select second repair option. I have kept the above incomplete.......so google it and if possible print the 1.5 page of instructions out. If you have the print out...you shouldn't miss a step and it will replace any missing or corrupted file. This is a level 1 of 10 in difficulty....very easy