I changed PSU to an older perfectly working one i had upgraded from, same problems. Memory still tests fine.
Possible motherboard problem? video isnt corrupted, sound is fine, no disk errors upon scans with manufacturer drive tools, drivers updated, windows updated. no usb attachments other than mouse which worked fine on old PC last month, same dvd drive from old machine with no problems.
current PSU:Coolermaster 460w - same issue
"new" psu Thermaltake 850-Watt TR2 RX - same issue