I have a pair of hp xw9400 boards in custom builds. i am having trouble installing any os with dual opteron 2431 hexacores. it'll post and go into bios just fine. when i run my install media it will load the installer and then shut off. it doesn't do that with quads. also if i add more than 8gb of ram they try to boot and after reading up to about 4000 some mb they shut off. if i run 8gb or less they run fine. whats wrong. also both are tested with vista and 7 as well as esxi 6.5 and server 2008 r2 wich
ALL work with 8gb ram and quad core cpus just NOT more than 8gb ram and hexacores and have the latest bios v4.03 AND are bought BRAND NEW IN THE WRAPPER!!!!!