Mirlas - it's ok. i have 4860HQ processor (3.6Ghz quad ) and load goes up to 75% when i run it.
it's normal because of load of threading and variables that are updated each tick. which means 75x second each variable has to be updated on my pc (if your refresh rate is 60 then 60 times).
anyway point is that if you follow 3000 variables x 75 = 225000 updates per second. and now each variable takes (For example 10 - 100 ops ) = 2 - 22.5 millions of operations per second. hard for cpu it is.