Try lowering HTLink, raising CPUNB and see if you can get that vcore under control. Heat is your enemy on these, less heat less voltage needed. I never had a Kuma core though. Closest I would say I had to that is the 9950 (Both are Phenom I ) the 1090 is going to blow your mind after practicing on that Kuma core

Hell the 550/555BE will blow your mind after that LOL
CPUNB will probably crap out around 2400 on that gen... on air/water and not much further colder IIRC...
When is the competition? I need to pick up a cool running AM2 chip for my nieces PC I just built her (have the 555BE in there now but its not "recognized" ) I can send you my Crosshair III and 555BE to practice on. Board is fresh from RMA new mobo this time instead of repair to old...
Depending on your sticks, 500 4-4-4 should be easily doable even on that old ass IMC.
EDIT: 1:1 HTL/cpuNB for wprime? interesting.... it is worth a shot. Vantage CPU test definitely sees an improvement in dropping HTLink... (and raising CPUNB of course) and that is multi threaded... try it though.