what can I do? My mbp is only using one thread of one core

[jlegere]

I just had to reinstall lion on my 2010 mbp ( the DC I5 520 )

After that I am using only one of the 4 threads available.

Anyone know a cure?

[GGJstudios]

I just had to reinstall lion on my 2010 mbp ( the DC I5 520 )

After that I am using only one of the 4 threads available.

Anyone know a cure?
Mac OS X manages CPU usage automatically. It will use what it needs, when it needs it. There's nothing you need to do.