Gulftown: Hexa-Core for Your Desktop
It’s no secret that both Intel and AMD have abandoned the megahertz race long ago, instead focusing on threaded performance. Programmers have followed, making applications as threaded as possible, which makes full use of every bit of computing power a CPU has.
That fact is emphasized with today’s look at what will be the first six core desktop CPU to hit the market when it is released in a few weeks – Core i7 980X Extreme. It certainly is extreme in one way, costing $1000 USD in 1000 unit quantities, but it is just a sign of things to come. Other Gulftown CPUs will eventually be released in the Core i7 series.
The 980X Extreme is the first Gulftown CPU to be released, which uses the same 32nm Westmere process technology we saw with Clarkdale (Core i5 and Core i3). Unlike Clarkdale though, it does not include an integrated graphics processor, nor does it use a 55 series IOH. Instead, it uses the regular triple-channel X58 IOH, and is fully compatible with all X58 motherboards after a BIOS update.
The die is laid out pretty much the same as original Nehalem (you can take a look at this die map for comparison), so no surprises are to be found. It is simply six 32nm cores with 12MB of total L3 cache shared between them. The picture above makes it look like 6MB is shared by a trio of cores, but this is not the case; the entire 12MB of cache is shared among all six cores.
The memory controller remains the same as Nehalem – a triple-channel controller, supporting DDR3 1066 memory. This provides 25.6 GB/s of bandwidth, which shouldn’t prove to be a limitation. The QPI on the Core i7 980X runs at 6.4 GT/s, just like other Extreme Edition Nehalem CPUs. Even though the die has been shrunk to 32nm, the TDP remains the same as the previous Extreme Editions – 130 Watts – because there are two extra cores on die. The 980X comes clocked at 3.33 MHz base, with turbo reaching up to 3.60 GHz in single-threaded operations. These speeds are identical to the 975 Extreme, as are the turbo settings (CPU ratio is increased by 1x for 2, 3, 4, 5, and 6 core loads, and 2x for a single core load), so it isn’t as aggressive as Lynnfield’s Turbo settings.
You can probably determine by now that Gulftown is quite simply a Nehalem CPU, in a 32nm package, with 2 extra cores. Just about everything works the same, including Turbo Boost, HyperThreading, etc. You can read about all that in our original Nehalem review. One addition that was made is AES-NI encryption/decryption acceleration, which adds 12 new processor instructions that can significantly improve performance (when these instructions are actually used – we’ll get to that later on).
Since not much else has changed, we can get right to the performance results!