Twin Quad Core Xeons - Only One shows!

[RazMan]

I have an HP XW6400 (dual cpu motherboard) workstation which has been running fine on a single Quad Core Xeon processor. Today I decided to fit a second Xeon cpu and was suprised to find that although it was detected in the bios, Windows 7 seems to still only show one cpu in Task Manager. Device Manager however detects all 8 cores (count 'em folks ) Also diagnostic progs like Sisoft Sandra only see one processor (4 cores)

Am I missing something here?

p.s. Win 7 Ultimate x64

 

[Tews]

Go into msconfig/boot/advanced and tick the processors to two ... hope this helps...

 

[RazMan]

Thanks for the tip - however that just reduced the number of cores to two!
So just to experiment I reduced it to one and now I can't even bring back any more cores - I'm stuck on ONE CORE now

MSConfig is obviously the source of my problem but how can I reset it to get all of my cores back?? (I'm still showing 8 cores in Device Manager)

 

[RazMan]

I've sorted it now

I had to reboot a couple of times while resetting msconfig to 'normal startup' and all of my cores magically returned - all 8 of 'em.

btw the 'number of processors' in the boot options is definitely referring to the number of cores - and boy does having 8 make a difference! My index rating jumped from 6.8 to 7.4 so my hard drive looks like it is holding me back now - SSD will be ordered shortly.

Thanks for pointing me in the right direction Tews, even if it made me panic at first