|MSI Z68A-GD80 Intel Motherboard|
|Reviews - Featured Reviews: Motherboards|
|Written by David Ramsey|
|Wednesday, 01 June 2011|
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The Intel Z68 Express Chipset
Although the Z68 chipset had been rumored for some weeks, it's still a little surprising how rapidly it appeared after the introduction of the P67 chipset. This architecture diagram summarizes its features:
If you're looking at this diagram and thinking "This looks just like the P67 Express block diagram", then you're right! There are only two differences:
Everything else is the same; disappointingly, Intel has not given us any increase in the number of PCI-E 2.0 lanes, which remain at 16 from the processor plus 8 from the chipset for a total of 24. Compared to the 40 lanes available on an X58-based system or the 42 lanes available on an AMD 890FX system, the Z68 still comes up short. Users running multiple graphics cards are limited to 8 PCI-E lanes per card with two cards, or 8x4x4 with three cards. While tests have shown that there's very little degradation in performance with 8x8 dual-card systems as opposed to 16x16 systems, enthusiasts tend to look askance at limitations like this, even though they might be of little real-world significance.
But there can be some less obvious effects: remember that PCI-E lanes are also used to support SuperSpeed USB 3.0 and SATA 6Gbp/s ports, and the Z68 has four of each. If you're running multiple graphics cards, several SATA 6 devices, and several USB 3.0 devices, you're going to run out of lanes (which will be taken from the PCI Express slots). Granted, not many users will run into this limitation, but some will.
Aside from the paucity of PCI-E lanes, though, it's all good. The Z68's most significant new feature is its support for integrated Sandy Bridge graphics even when one or more separate graphics cards are installed. This has several advantages: on its own, it means you can run two monitors directly from the motherboard, or four or six with one or two separate graphics cards. With Lucid Virtu technology, you have power savings when the performance of the separate cards isn't needed, and the ability to make use of Intel's Quick Sync video transcoding feature even if you have a video card installed. Benchmark Reviews examines Virtu technology in detail in a separate article.