The current P4Cs might be good value but they won't hit speeds you've been seeing. A friend of mine has a 2.8C D1 stepping that can OC a whole ghz and still boot into windows. Not to mention do 3.6Ghz stable @ 1.55V.
Of course he purchased it around this time last year and the price was double then.
Intel's earlier P4Cs have more OC headroom than these newer ones. For a new 2.8C to hit 3.3 is pretty much all they can do @ default voltage. So if you purchased a 2.8C recently, there's absolutly nothing wrong, your CPU quite simply isn't capable of the speeds you've seen in the past.
The hot OC CPU right now is the 3.0C SL6WU
I have an sl6wk 3.0c (30 caps) and I am currently @ 3.63 1.56 voltage
Yeh I've got the 30 cap 3.0C as well: my
SL6WU, manufacutred 1/20/2004. This one does 1.525V (default voltage) @ 3.66Ghz prime stable. It was from an older shipment which I tracked down @ work. The newer shipment that we got were all the castrated 15 or so caps and I know for a fact they don't do more than 3.45 ghz stable unless you overvolt it heaps (and even then it's still unstable). Tried a few for "testing" purposes
Now if I bought a 3.0C say 9 months ago, that thing would OC like a champ and hit 3.8 on air and default voltage. Ah well, it woulda cost nearly double so it evens out.
i have trouble hitting 3.5 with my 2.8c.
Don't dissapointed with your 2.8C. I keep seeing people complaining about their CPUs not being able to hit speeds others can do. The newer your D1 stepping P4C, the less it will OC. It's nothing to be dissapointed about, considering the older P4C's were purchased at a higher price than what you recently paid for yours.