That doesn't sound like it's off by much, maybe 1-2'C. Before I OC'd my opteron 148 I was reading idle temps at around 23'C and load temps at around 27/29'C, granted it was cold on those days. I've OC'd to ~2.9ghz and my idle temps are 27/28'C with loads peaking at ~38/39'C.
I'll admit that...