Occasionally i get the dreaded blue screen when usung Vista Ultimate 64bit This can happen at any time and not during running anything specific. The message is MEMORY_MANAGEMENT. My system specs are as follows as someone may know the cure!!! Windows Vista Ultimate 64bit with SP1 Gigabyte GA-X48T-DQ6 mainboard Intel Core 2 Quad Q9300 2.5ghz 8 gig of OCZ Reaper X PC10666 10333mhz memory. 4 Dimm's of 2gig each. Nvidia MSI N9800GX2 graphics Coolermaster Real Power 1250watt PSU All equipment is brand new and this problem is a real pain. Someone may be asking is the memory i have fitted in the list of memory supported by the mobo manufacturer. Well this specific memory i am using is not but the spec of it is if this helps. Phil.