|A lot of thanks to both of you for prompt responses.|
After trying connecting another 80GB HDD to the Vectra VE, I found the same result, i.e. hang at BIOS checking the capacity of the drives.
Searching for BIOS update, I found a website discussing the same problem with someone quoting from HP FAQ of another model that "The BIOS can handle hard disk drives up to 33.8 GB." and "HP does not plan to release an updated BIOS to increase this limit." I followed the quote and found that it's true of my model too. They didn't say that in their BIOS update page :(
So, I consider the case closed.
Thank you for your kind help.