In our testing we used a £135 Athlon 64 X2 5000+ on the Asus M2A-VM and compared it with a £325 Intel Core 2 Duo E6700 on an £85 Intel DG965OT motherboard. Not a direct comparison, true, but that was the hardware we had to hand.
PCMark05 1.2 Benchmark Results
The E6700 CPU has about 25 per cent higher performance than the X2 but broadly speaking when you run on integrated graphics the two platforms are very similar, even though the Intel combo costs considerably more than the AMD set-up. The area of separation is gaming on integrated graphics as the Intel G965 chugs along while the AMD 690G manages the job with some aplomb.
3DMark Benchmark Results
Plug in a £115 Sapphire PCI Express Radeon X1950 Pro graphics card and Intel wipes the floor with AMD, just as you'd expect.
Half-life 2 - Lost Coast Benchmark Results