http://forums.uktrainsim.com/viewtopic. ... 9&t=118677
In particular is the option (checkbox) for Multi-Core.
Note the red arrow pointing to the Multicore setting. This should be left OFF for most people. It appears to enable a workaround for some broken power-management features under Windows XP, but there are better ways of fixing that without the side-effects. Very few people wil see a performance increase from the Multicore setting - it does not turn on or off the new multithreading features - but it can overload your CPU and force it to slow down.
I think this thread will go a long way in helping folks get the optimal performance from RW3 for their system. Heck, it almost inspires me to give it a try and update to RW3.
