i'd consider it pretty damn unlucky to have one that can't do 4.4. That's not hype or bragging, just an observation.
I think it really comes down to:
1) What motherboard?
2) What voltage?
3) Are we only hearing about the successes?
Here's something that happened to me, BITD. From the heyday of socket 939 to the decline, I was purchasing 939 CPUs like crazy! Besides any number of 3400+, 3500+, 3700+, 4000+, FX-55, I also went through several Opteron 144 chips.
One of those chips would barely overclock.
Now, when anyone who was into overclocking thinks of the Opteron 144, they think of a 1MB cache 1.8GHz CPU that was a "guaranteed" 2.7GHz. Indeed two of mine did more like 2.9GHz.
The third one could barely go over 2GHz.
Yep, got a serious dud. 2.2GHz was the limit for even booting into Windows, and 2-2.1GHz was probably the limit of stability.
I posted about my experiences here, and the replies, shall we say, were less than kind. I got comments ranging from "you're using the wrong motherboard" to "you're using the wrong BIOS settings" to "you don't know what you're doing" to "you are an idiot."
I was using the same RAM, PSU, cooling and motherboard that I was testing the other two Opty 144, since I had them all at the same time. I think the board may have been a DFI Lanparty Expert. Not a slouch of a board, and the EXACT SAME SETUP took the other two chips to 2.9GHz.
That experienced was probably instrumental in turning me into a bitter man.

The comments were certainly instrumental in turning me into a "lazy" overclocker (doing "safe and easy" overclocks for just a free boost, not going for highest/edge of stability).