We've already reviewed a couple of 45nm Yorkfield quad core processors, and while the performance has been exceptional, most readers were chomping at the bit for the dual core Wolfdale to make its long-awaited appearance. The reasons are obvious, as most of the Yorkfield models are pricey, and most desktop users will be better served with a higher-clocked dual core processor anyway. The Core 2 Duo is also more suited to higher clock speeds than a similar-generation Core 2 Quad, and at 45nm, the Wolfdale looks perfectly suited to set some records in the overclocking field.
The Wolfdale core is the other half of the 45nm Penryn family, the dual core counterpart to the Yorkfield quad. Like the Yorkfield, the Wolfdale is based on 45-nanometer (nm) High-k metal gate silicon technology, which uses a combination of high-k gate dielectrics and conductors, rather than silicon, to build the transistor gates. A prime advantage of this technology is faster transistor switching speeds, but at reduced power, which in turn allows higher processor speeds at a lower thermal and power envelope.
The Wolfdale is also not just a 45nm die shrink, but it brings some other advantages to the table. The 45nm SRAM process has allowed an upgrade from 4MB of L2 Smart Cache to a full 6MB per dual core. The L2 cache also has 24-way associativity, compared to only 16- way associativity on the 65nm Core 2 processors. This improves performance, as cache hit rates will be higher with 6MB of L2 compared to only 4MB, and the 24-way associativity upgrades this even further. The Wolfdale also includes the latest microarchitecture enhancements, enhanced power saving, and support for SSE4, Super Shuffle Engine, Enhanced Intel Virtualization Technology, and Fast Radix-16 Divider.
The Core 2 Duo E8500 is built on the 45nm Wolfdale core, and features 6MB of Advanced SmartCache, which is shared between the cores. This is a true dual core architecture, as opposed to the dual Wolfdale cores on a single Yorkfield processor package. The Core 2 Duo E8500 uses the LGA775 processor interface, and offers basic features like Execute Disable Bit, Intel EM64T, and Enhanced SpeedStep.
Its 3.16 GHz clock speed places the Core 2 Duo E8500 right at the top of the dual core heap, just ahead of the 3.0 GHz Core 2 Duo E8400 and 2.66 GHz E8200. But unlike some of the top-end Yorkfield quads, which used FSB1600, the Core 2 Duo E8500 sticks to FSB1333 and a 9.5 CPU multiplier. The processor runs at a default core voltage of 1.225V (min: .825V) and has a thermal specification of 72.4°C, while the TDP remains at an amazing 65W.
The upgrade potential of the 45nm Wolfdale is also much better than its Yorkfield quad core sibling, as there is no requirement for FSB1600 and even the 680i SLI boards that are incompatible with the Yorkfield do not have the same issue with the dual core Wolfdale. Usually, all that is required is a BIOS update, if only to properly identify the new processor and ensure full support for its feature set.
