HP Pavilion Laptop booting Problems

Hi,

I have a HP Pavilion tx1220us Notebook. The computer boots up at times. After several tries, it boots up. I did a system recovery, and no such luck. I tested the hard drive, and it passed. I removed the memory modules and the hard drive, and I still could not get it to boot up right away. When It boots up, it works fine. It it only when I try to re start the computer. Yesterday I got to boot the PC up, and downloaded all the updates, I had no luck. It does not boot up by itself. The problem was when I had to restart the computer. The only way the computer would boot up was by pressing any of the keys F2, F8, F10 or F11. After several times trying different keys, the HP logo would came up. That is how I knew it was going to boot up with no problem. Once it boots up, it runs like a baby. When the computer does not boot up, the lights light up and you can hear the fan. You can hear the HDD, but then it stops. Other than that, I have no complains. It seems like I have to trigger the Bios in order for the computer to boot up. I don't know what the heck is going on, because once the computer boots up, runs normal. Thanks!