This bug also affects me. Tested on two X1 carbons, i5-3427U w/ 8gb and an i5-3317U w/ 4gb. Both fail at the 42~43% mark with a stream of errors.
Booting from xubuntu 12.10 amd64 usb (which has memtest 4.20) it fails.
I also tried from an xubuntu 12.04 amd64 usb (which also has memtest 4.20) and it passes.
This bug also affects me. Tested on two X1 carbons, i5-3427U w/ 8gb and an i5-3317U w/ 4gb. Both fail at the 42~43% mark with a stream of errors.
Booting from xubuntu 12.10 amd64 usb (which has memtest 4.20) it fails.
I also tried from an xubuntu 12.04 amd64 usb (which also has memtest 4.20) and it passes.