CPU faulty or just not supported?

[shafe88]

I was given a Athlon 64 X2 5600 to upgrade my Compaq SR5413WM, I installed the processor, and no post, or beeps, just a solid hard drive light with fans that slowly stop. I've tired it in my Optiplex 740 just in case it's not compatible with my Compaq and all's I get is a solid amber light with fans running at full speed.

 

[GhislainG]

The Compaq doesn't support it; according to Hp it supports Athlon 64 X2 with Dual Core technology up to 4800+ (up to 65 watt TDP). According to http://en.community.dell.com/support-forums/desktop/f/3514/t/19494756it should work in the Optiplex 740 if the BIOS has been flashed to a version that supports it.