Not that I'm aware of.
Grind for 6 - 8 hours with no slowdown or freezes.

Others will say there is a mem leak, but that is mostly a single user or 2 that report it.

ASUS M3N72-D
AMD Athlon 64 X2 5600+ Brisbane @ 3GHz
4 Gigs DDR2 PC6400 Dual Ch. Corsair
ASUS GeForce 9800GT 512MB x2 SLI
Win7 64bit or XP Pro x64