Safe 975x NB temps?

[WintersFury]

I've had this board a while and I'm sure the temps have been running far too hot on the NB at 65c. So since I'm running it more now and it's hotter out I poped the case open and zip tied in a fan kind of off of the HSF. Best I could do seeing how huge the Ultra-120 is.

I got my temps down to 55c. Which seems fairly safe (and in any event a very nice improvement) since I'm remembering the 975x to use a fair bit of power and not be the coolest running thing out there.

But what would be concidered "safe" temps for the chipset?