AMD's Phenom II processor is designed to boost the company's presence in the desktop market. But how does it fare against Intel's latest Core i7 (Nehalem) chip?
Intel has been manufacturing desktop processors using the 45-nanometre (nm) feature size since November 2007, but it wasn't until over a year later that rival AMD began to distribute chips manufactured using this process — currently the most advanced in mainstream processor production. Shanghai processors for the server market have been produced at AMD's Dresden factory since November 2008. AMD was delayed because of problems with 45nm manufacturing and Silicon-On-Insulator (SOI) technology. These difficulties have now been solved and the desktop variant, Phenom II, is ready for market.
With the move to 45nm, AMD can now clock the Phenom II processors at significantly higher speeds than their 65nm predecessors. At 3GHz, the Phenom II X4 940 is the fastest variant (its Phenom equivalent ran at 2.6GHz). Despite higher clock speeds and an increase in transistor count to 758 million (from 463 million) by doubling the Level 3 cache, the new CPU's power consumption remains unchanged at 125W.
The Phenom II is pin-compatible with its predecessors, so all that's needed to upgrade to Phenom II is a simple BIOS update of an AM2+ socket motherboard. Most of the larger motherboard makers — including Asus, Gigabyte and MSI — published compatibility lists in December. Along with the Phenom II X4 940, a 2.8GHz 920 model is also available.
Test models and platforms
For all the tests of AMD's new processors, we used the MSI DKA790GX Platinum motherboard with an AMD 790GX chipset. The Intel Core 2 Duo E8500 and Core 2 Quad Q9550 processors operated on a Gigabyte GA-X38T-DQ6 motherboard, while the Nehalem Core i7 920 chip used a Gigabyte EX58-DS4 board.
For main memory, the AMD systems used two 1,066MHz OCZ 2GB DDR2 modules. These chips do not adjust themselves automatically in the BIOS to the frequency specified by the manufacturer, but have to be manually set to run at the higher speed. We also had to increase the voltage to 2.2V.
The Intel systems with Core 2 Duo and Core 2 Quad CPUs used two 2GB Aeneon DDR3 modules running at 1,333MHz, while the Nehalem system used three 2GB Aeneon modules running at Intel's recommended DDR3 speed of 1,066MHz. For comparative purposes, the differing main memory sizes of 4GB for the Core 2 Duo, Core 2 Quad and Phenom II systems against the Core i7 920 with 6GB had no bearing on the test results.
We used an ATI Radeon HP 4870 graphics card with the 8-561-3-081217a-73402 driver and a Raid-0 array of two 250GB Western Digital disks for storage. The systems ran Windows Vista 64 SP1.