AMD FX-62 review

Although AMD has made significant advances in many areas, its processors have lagged behind Intel's in one regard: memory support. While Intel motherboards have supported DDR2 memory for a couple of years, AMD has supported only DDR memory.

AMD integrates the memory controller on the processor, so to add support for DDR2 it had to update this memory controller and introduce a new processor socket. This is exactly what AMD has done with Socket AM2 and its new line of processors, which includes the FX-62. AMD will fill out the product line with the new Athlon 64 X2 5000+ and AM2 versions of the X2 4800+, 4600+, 4400+ and 4200+.

At first glance there's little physical difference between AM2 and the current Socket 939 chips. However, closer inspection shows that AM2 has 940 pins, so you can't plug an old processor into a new AM2 board, and vice versa. It's not just the socket that has changed, though. The surround, to which the heat sink and fan connect, is also different. The new design has a single central lug for heat sinks to connect to, compared with the three-lug design of Socket 939. While we managed to connect an old AMD reference fan to the new design, a lot of other heat sinks will be useless, especially those that require all three lugs. As the new surround is fixed to the board with four screws, one in each corner, old heat sinks that screw to the motherboard won't work as the old design uses two central screws.

For most of us, though, the new design shouldn't cause any problems. It's the addition of DDR2 memory support that makes AM2 interesting. Despite having higher latency than DDR memory, DDR2 can run at much higher speeds, providing quicker access to data. As AMD's processors have direct access to memory, unlike Intel's processors, which have to go through a separate memory controller, the higher memory speeds reduce bottlenecks significantly.

For this review, AMD provided us with a test kit that included 1GB of 800MHz DDR2 memory. As you can see from our test results, the processor flew through our tests, producing the highest score we've ever seen. Unfortunately, PCMark04 refused to run one of the tests and we couldn't locate the cause of the error.

In the tests that did run properly, the Athlon FX-62 was clearly streets ahead of other processors we've tested. We would expect it to be fast, as it has two cores running at 2.8GHz (200MHz per core faster than the FX-60) and 1MB of L1 cache.

The move to DDR2 memory is long overdue and the FX-62 has announced its arrival in style. It's by far the quickest processor we've seen. However, it's very expensive and because of the socket AM2 you'll need a new motherboard, memory and perhaps even a heat sink and fan. If you've got a Socket 939 motherboard, it would be better to upgrade with a faster 939 processor. If you're building a new system, though, you'll be very pleased with the AM2.