Intel Core i7 CPU tested

If you've followed Intel's chip designs over the years, the term 'hyperthreading' shouldn't be unfamiliar. This technology lets Intel simulate more processing threads on top of its old dual-core Pentium 4 chips. It abandoned that strategy with the Core 2 family, but Intel has resurrected it with Core i7, and it's why you'll see eight processing threads when you bring up Windows' system performance screen.

Few day-to-day programs will benefit from hyperthreading, and it's more of a situational benefit for processing reliability and the scant few applications that can actually support so many threads. Core i7 will eventually hit eight native cores on a single CPU, or 16 processing streams with hyperthreading, but Intel has not made it clear when that will happen. It may be worth the wait, if you know you'll need that much parallelism, but few consumers will.

Multigraphics agnostic

Another significant change with the Core i7/X58 landscape had to do with graphics cards. Intel's Skulltrail platform of last year supported both standards as well, but the specialised CPUs that made the board worthwhile were prohibitively expensive. With the X58 chipset, yes, it comes on an expensive motherboard, but you can purchase a Core i7 chip to go with it for less than £250. The Core 2 Extreme QX9775 Skulltrail CPU started at £1,250. Gamers who stay current with graphics cards should be especially happy with this flexibility, as changing 3D card vendors will no longer require a wholesale system rebuild.

We tested both SLI and Crossfire setups on our Core i7 test bed and found both worked without trouble, requiring nothing more than installing the hardware and appropriate graphics-driver software as you would normally. As for their performance, AMD has issued a series of so-called 'hot-fix' drivers to improve the compatibility and frame rates of its cards with various PC games, which suggests that its software still needs to work out a few kinks on X58. Nvidia has not been shy to point out this fact (its beta drivers have worked fine), but we also find it telling that all three of the high-priced Core i7 gaming desktops we're currently looking at come with multicard AMD configurations.

h2> A quicker pathFinally, the last major change with Core i7 is the introduction of what Intel's calling the QuickPath Interconnect (QPI). Essentially this is the Intel version of AMD's HyperTransport interface between the CPU and the chipset. The major impact of the QPI for consumers is that Intel uses different QPI ratings to distinguish the Core i7-965 Extreme Edition from the non-Extreme Core i7 chips. Rated by Gigatransfers per second (Gigatransfers, or GT, refers to a million transfers of data), the Extreme Edition comes in at 6.4GTps, where the non-Extreme versions handle only 4.8GTps. In addition to that speed advantage, Intel also ships the Extreme version with an unlocked clock multiplier, which means it can be overclocked. The standard Core i7's will have to remain at their shipping speeds.