I get the SQUASHFS error: sb_bread failed reading block while trying to boot from a known good 8.04.1 LiveCD
.... as per Dimitrios' suggestion memtest shows that my second memory module has gone bad - doh!
Removed the bad module and all is now working.
So for me the error (same as for the original poster) _was_ due to bad memory.
I get the SQUASHFS error: sb_bread failed reading block while trying to boot from a known good 8.04.1 LiveCD
.... as per Dimitrios' suggestion memtest shows that my second memory module has gone bad - doh!
Removed the bad module and all is now working.
So for me the error (same as for the original poster) _was_ due to bad memory.