X-bit labs

Intel V8 Eight-Core Platform Preview (page 3)

Category: CPU

by Ilya Gavrichenkov

[ 05/18/2007 | 06:57 PM ]

Just like the Core 2 Quad and Core 2 Extreme processors you are more familiar with, the quad-core Xeon CPUs consist of two dual-core dies put into the same package. Each of these dual-core halves features a shared 4MB L2 cache for both cores. So, quad-core Xeon processor has two L2 caches with the total size of 8MB.

Here I would like to remind that unlike its primary competitor, Intel considers this dual-die design of their quad-core processors to be more optimal from the economical standpoint. According to the company reports, the use of components parts with smaller die size increases the production yields by 20% and hence reduces the processors production cost by 12%. However, this approach also has another side to it. Ensuring cache coherency in one quad-core processor with two separate L2 caches will load the processor bus very heavily, because the data between them is transferred through system memory.

The complete list of Xeon X5365 specifications looks as follows:

As you can see, the stepping of quad-core Xeon Clowertown processors coincides with the Kentsfield stepping, which is another proof that they are close relatives.

You can also notice that the core voltage is pretty high, too. It is higher than Vcore of any other existing processors with Core micro-architecture. As a result, the typical heat dissipation of Xeon X5365 has also grown quite high and hit 150W. This high heat dissipation reminds us of the times of NetBurst at least in the server segment, especially since the TDP of those Xeon processors didn’t exceed 130W. However, they set the TDP to 150W only for the 3GHz model of the quad-core Xeon Clowertown family. Slower CPUs boast lower TDP of only 120W.

Intel suggest using specially designed all-copper coolers to cool these pretty powerful Xeon X5365 processors:

Of course, they are quite heavy that is why they are installed using special backplate retention.

Note that there is no info on Intel’s official web-site today about Xeon X5365 processors. They are currently being shipped in limited quantities exclusively to very few system builders. These quad-core workstation processors working at 3GHz frequency should become widely available in Q3 2007.