It's a sign of just how far prices for DDR2 have fallen that Corsair's once prohibitively priced Dominator RAM is available for less than £100.
Given the overclocking potential of Core 2 and Phenom chips, though, there's a convincing argument for stretching to buy the famous DHX heatspreader.
Unfortunately, we ran into problems with the Dominator from the off.
Even without the FSB cranked up for a comparable test platform to the 4GB kits, we couldn't hit the quoted 1,066MHz speeds at 5-5-5-15. The best we could manage was 900MHz.
Even if this was just a curiosity of our mobo, the main conclusion stands: four gigabytes of slower RAM outperforms two gigabytes of performance stuff like this in all our practical tests.