Verdict: Dual-core for £100
With Intel's Core architecture grabbing all the headlines, AMD's position as the CPU manufacturer of choice for most enthusiasts is under threat. AMD's response has been to drop its prices like they're going out of fashion, and you can now pick up a dual-core Socket AM2 Athlon 64 X2 3800+ for a tempting £106.
For anyone still stuck with a single-core processor, the low prices of Socket AM2 dual-core CPUs may seem like the perfect excuse to upgrade. However, with affordable Intel Core 2 Duos, such as the E6300, now hitting the market, is Socket AM2 the way to go?
The Athlon 64 X2 3800+ has two cores, both clocked at 2GHz and each with 512KB of Level 2 cache. While a total of 1MB of Level 2 cache sounds impressive, by today's standards, the X2 3800+ looks slightly undernourished in this department. Intel Core 2 Duos such as the E6300 benefit significantly from more cache, and the fact that it comes as one large pool shared between both cores, rather than two discrete chunks.
Aside from requiring DDR2 memory, with its stock FSB of 200MHz and multiplier of 10x, the Socket AM2 X2 3800+ is almost identical to its Socket 939 namesake; it offers dependable, though not outstanding, performance in everyday tasks.
At its stock speeds, the X2 3800+ achieved a decent score of 1.21 in our Paint Shop Pro test. The Athlon 64 is a short-pipeline CPU, and has always struggled slightly with our DVD encoding challenge, so the X2 3800+ only managed a score of 1.03 in this test. However, it redeemed itself in the multitasking test with a good score of 1.49. Its overall score of 1.24 is very respectable, making the X2 3800+ good value for money at just £106.31.
Unfortunately for AMD, the Core 2 Duo E6300 easily outperforms the X2 3800+ at stock speeds, scoring 1.33 to the AMD's 1.24. However, overclocking could potentially offer a lifeline for the venerable AMD64 architecture.
The Asus Crosshair motherboard is the best overclocking board for Socket AM2 that we've seen, and it revealed that our retail CPU was willing to stretch its legs. However, to really push the X2 3800+, and give it a sporting chance of outperforming the E6300, a lot of voltage was needed. With a hefty 1.625V going through the CPU, the X2 3800+ was stable at 2.9GHz with an FSB of 290MHz, and it ripped through our Media Benchmarks. To achieve this overclock, though, we had to use a huge bank of 120mm fans to cool the CPU and motherboard, and this made such a racket that you'd be better off investing in a decent water-cooling kit.
Nevertheless, the performance boost was remarkable. The Paint Shop Pro test score increased from 1.21 to 1.64, DVD encoding rose to 1.41 and multitasking hit the heady heights of 2.04. For £106, an overall score of 1.69 is brilliant - just four months ago, the same amount of money would get you an Intel Pentium D 805, which scored 1.24 overall when overclocked. However, the Core 2 Duo E6300's overclocked overall score of 1.80 is better, and the Intel chip didn't require such a blistering level of voltage. The X2 3800+ wasn't so hot in the game test either; it kept pace with the E6300 at stock speeds, but fell behind when overclocked, and its average of 60fps was unable to match the E6300's 76fps in Need for Speed: Most Wanted.
As ever, there's no guarantee that your CPU will be willing to overclock to the levels we saw, but the X2 3800+'s 10x multiplier means that you don't necessarily need to buy an expensive overclocking motherboard capable of gargantuan FSB speeds in order to get the most from the chip.
CONCLUSION
For £106.31, a Socket AM2 dual-core Athlon 64 capable of hitting 2.9GHz is amazing value for money, and you can certainly build a powerful system based around Socket AM2 using a budget-friendly nForce 570 SLI motherboard such as the Abit KN9 SLI.
However, Core 2 Duo motherboards are coming down in price and, with a Core 2 Duo, you can use cheaper RAM. As there's only a slight price difference between the Athlon 64 X2 3800+ and the Core 2 Duo E6300, but a noticeable performance difference, there's really only one choice.
