AMD Bulldozer - FX 8150 Performance Review



Product: AMD FX 8150 / Asus Crosshair V
Company: AMD
Author: James Prior
Editor: Charles Oliver
Date: October 11th, 2011

FX Processors

Now you've seen the architecture and the marketing, what will you be able to buy? AMD plans a full line up of FX processors, all based on the Zambezi die using core disabling and clock speed adjustment to give different performance and price options. The model numbering for FX products use a four digit number to determine the classification of CPU. The first digit indicates the number of cores, with the FX-4000, 6000 and 8000 series indicating quad, sexa and octacore models. The last three digits indicate relative performance inside that series - an FX-8150 is higher performance than an FX-8120, but performance between FX-8100 and FX-6100 isn't directly comparable in the same manner. Like the original FX series, the new FX processor line up is CPU multiplier unlocked for easy overclocking.

FX Product Range

AMD is disabling core pairs due to the modular nature of the Bulldozer design - a BD module is 2 cores with 2MB L2. Looking at the above CPU line up you can see they are indeed disabling modules, as L2 cache totals drop with core count. Satisfyingly, the L3 cache remains intact as this is outside the BD module, so you get the same full 8MB on a quad core as you do on an octacore. The other item to notice is the Northbridge speed, which drops from 2.2GHz to 2.0Ghz on some models.

FX Launch Models

At launch there will be four models available for purchase, two octacores, one hexacore and a quad core. The FX-8150 is the current highest performance FX processor, running 8 cores at a base clock of 3.6GHz and all core turbo of 3.9GHz, and a 4.2GHz four core turbo. Priced at ~$245USD, the FX-8150 competes against Intel's Core i5 2500K, currently priced at ~$216USD (1K unit pricing).

In select markets the FX will be bundled with self-contained liquid coolers.

The FX-8120 is clocked slightly lower, with a 3.1GHz base clock with all core turbo of 3.4GHz and max turbo of 4GHz even, and priced slightly lower at $205USD, pitting it against the Core i5 non-K edition. Next is the FX-6100, the first FX processor with a disabled module, running six cores at 3.3GHz (3.6GHz all core turbo, 3.9Ghz max turbo) but also with a lower TDP, dropping from 125W to 95W. This is estimated to cost around $165USD which puts it up against the Core i5 2320.

The FX-4100 is, as it names suggests, a quad core CPU. This CPU has a 2GHz northbridge and 4MB L2 with a 95W TDP. Base clock speed is 3.6GHz, with an all core turbo of 3.7GHz and max CPU turbo of 3.8GHz; it has a price of $115. This positions it against the Core i3-2100, a 65W CPU with 2 cores, 4 threads and a 3.1GHz clock speed but no support for AES or VTd, which could be crucial in some segments.

Gaming Enthusiasts spend a lot of money on their hardware, but the amount is shifting - fewer systems are being built with a total system price tag of over $1500USD.

The heart of the Scorpius platform is the mainboard, which consists of an AMD 9-series chipset. Next we'll look at the ASUS Republic of Gamer's Crosshair V Formula mainboard we'll use to test the AMD FX processor.