These four systems each use two processors and the speeds aren’t a million miles apart from each other but the technology varies dramatically as you move up the scale.

The 2.4GHz Xeon 'Prestonia' is similar to Pentium 4 and supports SSE 2. Each processor has but one core though, thanks to Hyper Threading, it appears to have two.

Next we have the 3.0GHz Xeon X5365 which is a Pentium D-esque quad-core LGA771 processor that supports SSE 3.

The 3.20GHz Core 2 Extreme QX9775 isn’t a Xeon but you get two of ‘em on the D5400XS motherboard, and you can overclock Skulltrail to 4.0GHz with the minimum of effort. Quad core, no HT and SSE 4.1 for this one.

And finally we have the 3.2GHz Xeon W5580, which uses Nehalem technology and SSE 4.2. Each quad-core processor uses HT to show eight cores to the world which makes 16 cores in total.

Plenty of pins

We used an Nvidia GeForce GTX 280 with the three most recent systems, along with Windows Vista. But we had to take a different tack with the old Prestonia system. For one thing, the Intel 875P doesn’t support Vista - we used Windows XP Pro instead - and for another, the Asus PCH-DL supports AGP Pro graphics, so we used an AGP Sapphire Radeon HD 3850 graphics card. This doesn’t have any impact on our test results as the benchmarks have been selected to stress the processor, memory and memory controller rather than the graphics or hard drive.