Dell desktop Optiplex GX270 does not work after it has been stored

I have got a desktop Dell Optiplex GX270,,,,,it was working fine without any problem till I stored it in our shed room for a while.

Now when I boot the PC it hangs as shown in the snapshot below :
http://i49.tinypic.com/rkyihk.jpg



http://i46.tinypic.com/2dtwsir.jpg


About 5 minutes after the second screen above it says:

What I did
1- I upgraded the BOIS from A04 to A07
2- I could not find an option for BOIS default setup
3- I removed the motherboard battery for about half an hour
4- I removed one of the RAM stick
5- I can access CMOS by pressing F2
6- I tried to eliminate the possibility of a hardware that caused the problem I removed CD rom drive and floppy drive but no luck.
Thanks

 

so you are able to get into the bios .. Do you have a setup cd with XP or other OS install disk ?