Intel's new Xeon is blindingly fast

The new way is not to switch tasks, but to pull individual ops from each task as functional units open up. This gets a lot more done in far less time than with either the old way, or without SMT. Whereas the old version sometimes showed slight benefits, the new way is a clear win, with 10s of per cent better performance as the norm. If you are going to cast off a stigma, you might as well do it right.

Last up, we have turbo mode. There has been a bunch written about this, and much of it is wrong. The simple story is that based on several factors, the two most notable are heat and power draw, the cores can overclock themselves. Each core is independent, and can go up to three bins of 133MHz up from where they started. A 3.2GHz CPU will hit 3.6 on one or all cores, ambient conditions and load permitting.

Those are the big bangs, but there are enough detail changes like deeper buffers, more usable pipelines, and unaligned cache access to add up to a hugely fast and efficient CPU. VT-d, an enhanced hardware virtualisation method, not only brings the IMC into play for the first time, but also adds some I/O features into the mix. IOAT speeds up network access as well, freeing up more CPU resources to work on things other than packet twiddling.

The chipset is called Tylersburg, a new northbridge, although that is mostly a dead term because the memory controller is on die now, coupled with the older ICH9 or 10. It has 42 PCIe lanes, 36 PCIe2 and six PCIe1. If that isn't enough, you can add a second Tylersburg and nearly double that count. Should 78 PCIe lanes not be enough, you can't add any more now, sorry.

The usual ICH9/10 features are all there as well, including six SATA ports with software RAID5 support. Memory controllers are now on the CPU, but since we are used to talking about it on the chipset side, we won't break tradition now. The three DDR3 controllers can support up to DDR3-1333, with up to three dual-rank DIMMs per channel. This means 144GB of memory on a dual CPU configuration.

So, what do they end up looking like? There are 17 models that you can now buy, from 1S workstation chips to low voltage parts. Fifteen are quad core, two dual core, and the speeds range from 1.86 to 3.2GHz. Not all of them have the full feature set enabled, but most have the big ones available even if some are scaled back. QPI scales down on the slower models, and only the X- prefixed parts allow for the full three bins of turbo.

The gory details.