Hi Adrian,
Just a clarification. When you updated the BIOS and Vista, were you still able to boot successfully after that? When you boot, do you see any LEDs lighting up, do you hear the hard drive trying to spin and the CD/DVD drive initializing but all these stop after a few seconds? I am asking because the symptoms you described point to a corrupt BIOS.
About the SP1, I have doubts that you can uninstall SP1 when the laptop screen is blank.
When you power ON, do you go past the Compaq logo splash screen? Can you at least go into BIOS settings?
Here's a few things I need you to try...
- Reset CMOS. Remove the CMOS battery for 30mins at least.
- Remove battery and unplug AC adapter then press power ON button for at least 30secs. Put back the battery and plug in AC adapter then power ON as normal.
- Remove the hard drive and pop in a bootable CD in your CD drive. Power On the laptop and see if it boots from CD drive.