I'm pretty sure that I already know what the answer is here, but I thought I should post this anyway just in case I have overlooked something...
My laptop is a Toshiba Equium L40 (the 10X variant with 2GB RAM).
About a month ago I restarted my laptop and found that it was stuck at the BIOS screen, where I could hit F2 to enter the BIOS, or hit F12 to enter the boot menu. However, as soon as I hit one of the options the laptop would freeze. After a little fault finding I removed the internal HD and found that it would boot from a Live CD and let me access the BIOS menu etc. I pooped the HD back in and I was back to square one.
I tried the HD in another machine and it did the same thing, therefore I determined it must be the HD.
I bought a new HD and installed it and everything worked once again.
Since then my machine has been running perfectly with Windows 7 build 7077.
Today I downloaded the official Windows 7 RC build from Connect, stuck it on my USB stick and prepared to install the RC.
It booted straight away, I chose my drive for a clean install, it did the copying Windows files and then the expanding bit... All was fine until it restarted. It was stuck at the BIOS again! Exactly the same as last time.
Now I have tried a cold boot, removing the battery and power for a few minutes, removing the USB drive, booting without the battery, booting without power, and still nothing. I can press F2 or F12 but nothing happens.
I have never seen anything like this before, and I refuse to believe Windows 7 could do anything like that. What I find odd is that it had been working perfectly for a month or so, yet dies when I am installing an OS.
Does anyone have any ideas? I'm thinking along the lines of a bad HD controller or something sinister hardware wise... Being a laptop I don't really see what options I have other than trying a new HD, which obviously I have already done once. I'm not going to, nor can I afford to keep replacing the HD.
Is it a casualty of war?