Closer Look at Intel Skulltrail
Core 2 Extreme QX9775 Processors
Just like the previous prototype, Intel Skulltrail platform has very evident server roots. And in fact, this is not surprising at all. Classical desktop Core 2 Quad processors from Yorkfield family cannot work in SMP configurations; the LGA775 socket is not designed for that also. That is why Skulltrail uses special processors that are more like the new Intel Xeon CPUs from Penryn family. They formally belong to Core 2 Extreme clan but are designed in typical server form-factor: LGA771.
Intel Skulltrail platform uses two Core 2 Extreme QX9775 processors with almost the same characteristics as those of the Core 2 Extreme QX9770 CPUs for standard LGA775 desktop platforms. In other words, Core 2 Extreme QX9775 is a combination of two dual-core dies manufactured with 45nm process and equipped with 6MB L2 cache memory that are stuck together into a single packaging. The nominal clock speed of Core 2 Extreme QX9775 processors is 3.2GHz and the bus works at 1600MHz.
The complete list of Core 2 Extreme QX9775 specifications is given in the table below:
| Core 2 Extreme QX9775 |
Codename | Yorkfield |
Nominal frequency | 3.2GHz |
Bus frequency | 1600MHz |
Multiplier | 8x |
L2 cache | 2 x 6MB |
Cores | 4 |
Packaging | LGA771 |
Production process | 45nm |
Stepping | C0 |
TDP | 150W |
Vcore | 1.25V |
Enhanced Intel Speedstep | Yes |
Intel 64 | Yes |
Intel Virtualization Technology | Yes |
SIMD instructions support | MMX, SSE, SSE2, SSE3, SSE4.1 |
Transistors | 2 x 410 mln. |
Die size | 2 x 107 sq.mm |
Official price | $1499 |
There is nothing unexpected about these specifications. The only thing that catches your eye is probably the high TDP of 150W. However, in reality Core 2 Extreme QX9775 processors from the 45nm Penryn family do not really heat as greatly as you may have thought after checking out this spec sheet.
If we disregard the fact that Intel is trying hard to pass Core 2 Extreme QX9775 for a desktop solution, we will see evident relative connection between this CPU and Xeon X5482. In fact, the only thing that is different between them is the name.
CPU-Z diagnostic utility recognizes Core 2 Extreme QX9775 processor as Yorkfield, although we believe it would be more correct to give it a server name: Harpertown.
Although Skulltrail platform uses LGA771 processors, Core 2 Extreme QX9775 looks practically identical to CPUs for regular desktop LGA775 platforms.
Left - Core 2 extreme QX9775; right – Core 2 Extreme QX9770
However, you shouldn’t think that LGA771 and LGA775 are compatible: Intel made sure that you cannot install the CPU into the wrong socket by shifting the openings in the CPU base.
Left - Core 2 extreme QX9775; right – Core 2 Extreme QX9770
