Upgrading Compaq (CQ40-109TU) from Windows Vista to Windows 7

Good day to all.

I am upgrading my Compaq laptop from its default Windows Vista Home Basic to Windows 7 Ultimate RTM 32-Bit. My laptop model is CQ40-109TU.

I freshly install the Windows 7 and download all the recommended drivers and softwares from HP/Compaq site for my laptop model with Windows 7 32-Bit.

After finishing the installation of Windows 7, Avira antivirus and Windows Updates, my laptop starts up successfully. But after I install the recommended BIOS version F.55 A ( sp45765.exe), my laptop hangs at start up when Compaq logo is displayed, and it does not respond in any keys I press (like Esc, F8, F12, etc.) to view the BIOS configuration. It only beeps after pressing a key several times.

Also, I notice that my laptop does not charging too after the laptop restart. The LED on AC adapter has light, but the light where the adapter connects to my laptop is off. But there is a blinking light in the thunder icon while the charger is connected to my laptop. So, the charger is okay and supplies electricity to my laptop. But why the light, that indicates the laptop is charging, is off? Currently, the battery is drained already.

My laptop's previous and working version of BIOS is F.12.

What happen to my laptop? Do I miss something during my installation process, or the BIOS version F.55 A does not really compatible to my laptop? Is there any workaround for this problem? How can I restore my previous BIOS version F.12?

I am very hopeless, and I don't know what to do. Please help me.