FWIW, this version of Memtest86+, on a 350 MB Linux bootable CD,
http://www.sysresccd.org/Sysresccd-m...t_floppy_disks
spotted my HP TouchSmart TM2-1010 laptop as having bad memory
(one of two 2 GB modules) when Windows only gave me filesystem
error messages, and I think the laptop's own (EFI) diagnostic
said that the memory was fine. I assume that it's also happy
to check memory above 4 GB!
The memory was returning some wrong bits in certain places,
all across 2 GB of space. Apparently if you just have a few
bad bits in a memory module, you can tell Linux at least to
not use those memory addresses...
MemTest86+'s own ISO is available here. Their install-to-USB
tool may be more successful than SRCD's was for me. Then again,
some systems just don't like booting from a USB stick or SD card.
http://www.memtest.org/
Apparently one or more web servers with IP addresses /near/ to
www.sysresccd.org serves nasty software, and for that reason,
MalwareBytes and other security tools may report that SRCD is
a bad site as well. If it was mine, I'd probably move it,
and maybe they have - it was some time ago that I ran into
that condition.