CPUs > 500 GBP and more CPUs > by No. of cores

Advantages: Unlocked multiplier
Disadvantages: Price, same performance can be had with overclocked Q6600/6700 for less

...Back in the older days, Intel used to differentiate the Extreme editions from the standard Pentium 4's/D's with more cache or Hyperthreading. Since the Core 2 Extreme Editions have been released, the only aspect these have that can't be found on the standard Core 2 Duo's/Quads is an unlocked multiplier. Sadly that's the only feature and is it worth 2x the price, I think not!. a Q6600 G0 or even B3 can be overclocked way beyond 3GHz using a 8x or ... Read review

Advantages: Insanely efficient, SS4 instruction capabilities, unlocked multiplier
Disadvantages: fairly expensive, some more programs need to be multi threaded

...were looking very dire for Intel indeed. Massive job cuts, poor PR and above all they had an outdated series. Their main rivals AMD were trouncing them at every step. They left no stone unturned and Intel seemed to be in major trouble. Then the Conroes hit the market. Instantly the tables were turned. The new 65nm process Intel adopted, dominated the market. They ran cool, extremely efficiently and above all they overclocked. Fast forward to today ...
...overclocks even better than before. Intel knows what consumers want. Value for money. On my meagre rig ;) I managed to overclock the QX6950 to over 4.3Ghz on watercooling. Unfortunatly my motherboard cannot go anyhigher so for the time being im limited. However being the Extreme version, this chip allows you to drop the multiplier to negate the limitations of the other components. Would I recommend this chip though? Maybe. As much as I have raved ... Read review

Advantages: There is no faster CPU - future proof
Disadvantages: Price

I was eagerly awaiting the release of the core2 architecture last year but decided to hold out to see if there would be any bargains around Christmas time. This was also the scheduled release time of the quad core version. As the time neared I began reading reviews and seeing what programs would utilise all 4 cores and found that the list was short. However, for an equivalent price I could have bought the X6800 chip which although has a higher core ...
...proofing I decided to get the quad core. Before installing this chip a bios update was needed in order for my motherboard to pick up the chip and would fail to boot without it. Windows however does not need to be reinstalled and picked up all 4 cores perfectly and went about balancing the load from my running programs around all cores. I ran a few in game benchmarks against a friend with the X6800 chip and my QX6700 was noticably slower. However, ... Read review

Advantages: Extreme performance, very stable, low power consumption
Disadvantages: High price, in future I recommend 4 cores (distant future)

...of shared L2 cache , Intel really did a great thing for the consumers. The prices is still high but for those who can afford it is really the best dual core processor. Performance. The performance is best in all domains:games, multimedia, encoding, only loses in quad core specific applications and are few of them. Ease of Installation. Based on the socket 775, the installation is not very difficult but take care that the cooler's 4 conectors to ... Read review

Advantages: Blistering speeds
Disadvantages: Ideally needs Vista 64 bit but few software compatibility probems

Intel have really got it right with this CPU. It was easy to install and runs like a dream. To take real advantage of the power of this CPU it really needs the Vista 64bit version and there are few software compatibility problems now so it is worth taking the plunge. I've never seen software install so quickly on a PC as with this processor and running Windows updates, background tasks, processor hungry games etc. just doesn't have an impact on the ... Read review