It's probably unnecessary to remind you that AMD has had very few successful "firsts" when it comes to its Phenom line. The latest Phenom II X2 550 Black Edition is, thankfully (or should that be "finally"?), the exception to the rule. It's the first dual-core Phenom II chip - and its actually pretty damn good!
As it's a Phenom II, it's a dual-core of 45nm origins, and is very similar to its bigger triple-core (X3) and quad-core (X4) brothers, only with two cores disabled. This means that with special motherboards, there's the possibility of unlocking the extra cores, although there's no guarantee that they'll work.
The 45nm K10.5 design used by the X2 550 BE features a huge 8MB of common L3 cache - more than enough to act as a snoop filter for just two cores - as well as DDR3 and DDR2 support. Supported memory speeds are faster than the Athlon II: 1,066MHz for DDR2 and 1,333-1,600MHz for DDR3. Another advantage is that this is a Black Edition product - so the multiplier is unlocked for easy overclocking.
It comes clocked at 3.1GHz, and with effectively a DDR3 memory channel per core (in un-ganged mode), there's not only oodles of cache, but also tons of fast memory access too.
3.1GHz, 200MHz x 15.5
Core Count: Two physical
L1 Cache: 64KB data and 64KB instruction per core (256KB in total)
L2 Cache: 512KB exclusive data cache per core (1MB in total)
L3 Cache: 8MB L3 inclusive cache
Fabrication Process: 45nm DSL SOI (silicon-on-insulator) technology
Packaging: Socket AM3 (Socket 938)
Memory support: DDR2/DDR3
Thermal Design Power (TDP): 85W
Transistors: ~758 million
Die Size: 258mm²
Click to enlarge
All this will set you back just over £70; in terms of its Intel competition, this situates it between the Core 2 Duo E6300 at £64, and the pricier E7400 at £85. It's not just CPU price that you need to look at when making a buying decision though: the cost of the whole platform (i.e. motherboard, CPU and memory) is crucial. In this respect, the X2 550 BE does rather well. Pair it with an MSI 770-CD45 motherboard and 4GB of low latency DDR3-1333 and it costs just £189. However, for an Intel Core 2 Duo E7400, Gigabyte GA-EP45-UD3R and 4GB of DDR2-1066 (it's £2 more than 800MHz), you'll need to shell out £224 - £35 difference.
Even if you choose the E6300 instead, the total system is still £15 more expensive. It doesn't sound like much, but it's halfway to a good CPU cooler such as the Titan Fenrir. The AMD setup should have more legs too - AM3 is in its infancy, with an upgrade to triple- or quad-core available, whereas LGA775 is at the end of its life. That said, cheap Q6600s could be flooding the market soon as upgrade cycles come around. All this is worth keeping in mind as we take a look at how well the X2 550 BE performs.