Haven't tried it; old systems working fine with no need to build a new one right now. Downloaded it just in case to update my old version.
"Memtest86+ v6.00 final has been released!
Since the last non-beta version (in 2013!), it has been rewritten from scratch and is back to active development. Memtest86+ is still 100% open-source and 100% free."
MEMTEST ORG - newest version of memtest+
Tom's Hardware article
"Memtest86+ v6.00 final has been released!
MEMTEST ORG - newest version of memtest+
Tom's Hardware article