Multicore option and HDR?

So whenever i have multicore rendering on, my HDR is really funky. If i spin in a circle in the middle of the map, it doesnt gradually glow and slowly dim, instead it just goes from super bright to really dim. As soon as i turn off multicore rendering it glows and dims like it’s supposed to. The problem with leaving multicore rendering off though, is i lose about half the fps i normally get, causing it to be extremely annoying, and leaves me in a bind. Anyone experience this? I do have a quad core processor, and it’s clocked at 3.5ghz so i’m kind of confused.

I believe that Multicore rendering ain’t perfect yet, but should be working fine on 64bit computers. Is yours 32 or 64bit?

64bit windows 7.