Massive CPU taxing during gameplay

When I start the game, it loads fine but for the first few 10-20 mins of gameplay the CPU is taxed 100%. My current GPU is an HD 7750 DDR3 2GB, RAM 6 GB, and a 500GB HDD (with a 120GB SSD)
During this period, if I modify a parameter of a car (say the gearbox spacing or the cooling capacity) it causes the game to freeze for a few seconds and then go back to normal. The cars load fine, but this bug has
Eventually if the game is being played long enough it goes back to normal.

EDIT: CPU is an AMD Athlon II X2 255.

That sounds like some anti-virus is kicking in in the background and then at some point gives up :stuck_out_tongue:
Automation is very CPU heavy, but it definitely should not lock up like this with a dual core unless you run Windows XP, which we don’t support multithreading for.

[quote=“Killrob”]That sounds like some anti-virus is kicking in in the background and then at some point gives up :stuck_out_tongue:
Automation is very CPU heavy, but it definitely should not lock up like this with a dual core unless you run Windows XP, which we don’t support multithreading for.[/quote]

Windows 7 SP1. I’ll see if switching AVs fixes it, never trusted Norton anyway.
Edit: Nope! Seems to be slightly better, but not by much.

I run norton and win 7 and have no issues with it

Yeah, not much better with avast.
It may well be my CPU, as it’s slower than almost any non-ULP CPU on the market today.