a) make sure you only install the exact speed of CPUs as it orginally, anything else or just fitting 1 CPU will end in all fans running topspeed all the time

b) when you do have a matching set of CPUs you'll need to calibrate the system (requires some sort of Apple-diagnostics-CD, google might help) to stop all fans running topspeed all the time.

both the mainboard and the cpus im fitting are duel. no single cpu ones in sight.

@kronos "make sure you only install the exact speed of CPUs as it orginally"

so is it right to assume i cant have faster cpus then the original? if the board cam with 1,8ghz i cant fit 2.0ghz ?

could it be this one http://computers.tutsplus.com/tutorials/finding-hardware-faults-exploring-aht-apple-diagnostics--mac-60456

seems to come with MACOS discs? (Applications Install Disc 2 for computers shipped with 10.5.5 or later, otherwise Mac OS X Install Disc 1).

couldt find any usable here: http://www.info.apple.com/support/aht.html

xZiT

[ Edited by XzIt 14.09.2014 - 13:57 ]