Hello, first time posting here so I'll try to be very clear.

I have a Lenovo S10 Ideapad netbook which fails to boot to an OS. It shows the Lenovo splash screen and can get to the BIOS but it doesn't get to GRUB (was dual booting Ubuntu 9.10 and Win 7, was working fine for months, ie this isn't a new dual boot gone bad). After the splash screen it displays a flashing cursor in the upper left corner. Power cycled to no avail.

Here is what I have done trying to narrow the problem down:

The machine will boot to Ubuntu using an install/live USB drive, but only if ANOTHER hard drive is installed or NO hard drive is installed. The boot order always lists USB first. Also, there is a 2 gb RAM upgrade but I think that's fine; the Ubuntu USB drive boots fine with it, and "free" sees the whole 2gb of memory.

So it seems like the hard drive is bad. I was able to put the bad drive in a different laptop and mount it to recover files.

I'm ready to replace the bad hard drive, but I would like to know if this situation makes any sense. If the hard drive is bad, shouldn't I still be able to boot with the Ubuntu USB drive while the bad drive is installed? I would have expected the machine to boot into Ubuntu anyway even if with a bad drive, since the boot order lists USB first. But it seems that when the bad drive is installed, the machine ignores the USB drive and hangs with the flashing cursor.

Thanks for any ideas! Sorry for the long post, I just want to put all the info I have up front! Basically I'm going to buy a new drive, but I am mostly curious if this is a typical or at least not unusual situation.