I run knoppix 3.3, do nothing, logout, reboot
I load my usual gentoo-2.6.7-r11 kernel and get

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Mounting /dev/hda3 on /newroot failed: invalid argument
>> Could not mount specified ROOT, try again
>> The root block device is unspecified or not detected
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So I reboot and retry my 2.6.7 kernel... same problem... again and again

So I reboot to my older gentoo-2.4.20 kernel and it loads fine, and

So I reboot and retry 2.6.7 kernel and now it works... and now I'm puzzled

Proceeding a startx and my nvidia driver only works for an awfully poor resolution. Reinstalling the driver does nothing.

I reinstall the kernel, the video drivers, and now all is fine.

In addition I can replicate this... obviously it's a painful thing to replicate but I can replicate it. Any ideas as to what is going on?