Why AMD's Launch of New Quad FX CPUs Means Little to Consumers

Late last week AMD launched their new line of quad-core CPUs to compete directly with Intel's Core 2 Extreme QX6700. Three versions of the Quad FX line were announced - the FX-70 running at 2.6GHz, the FX-72 running at 2.8GHz, and the flagship FX-74 running at 3.0GHz. Pricing was set at MSRP of $599 for the FX-70, $799 for the FX-72 and $999 for the FX-74.

The CPUs are compatible only with a newly released chipset - the NVIDIA nForce 680a - and will require a new motherboard in order to use the new CPUs. At the launch date, only one motherboard was available with the new nForce 680a chipset - the ASUS L1N64-SLI WS. The biggest difference between AMD's Quad FX line and the Intel QX6700 is the manufacturing approach used to reach quad-cores. The Quad FX uses two distinct dual-core CPUs to achieve a quad-core implementation, while the Intel QX6700 is a single CPU made of 4 cores built-in. The Intel QX6700 is an evolution in the line of Core 2 Duo line of processors, and thus it is based on the LGA775 platform. This means that nearly every socket LGA775 motherboard will support the QX6700 - a big win for Intel considering the cost and effort required to upgrade to a brand new motherboard. In terms of performance, the AMD flagship Quad FX-74 manages to keep up with the Intel QX6700 in most multi-tasking scenarios. It provides no benefit in gaming performance and actually lags behind the QX6700 in most games.

Since there are no games available today that will take advantage of the power of 4 CPUs, the Core 2 Duo Extreme X6800 is still the best CPU available for gaming performance. What really separates the Quad FX and Intel QX6700 is the amount of power each uses - both at idle speeds and under load. Because the AMD Quad FX lineup is utilizing two separate CPUs, the total amount of power used is twice as much as the Intel QX6700. So, to achieve approximately the same performance as the Intel QX6700, the AMD Quad FX needs 100% more power. Yes, you read that correctly - 100% more power!

In most systems, to support the power hungry Quad FX an upgrade to a new power supply would also be needed. A beefy 750W power supply would be just about the minimum I would recommend and a quality power supply of that caliber is going to run you at least $200 at current prices, and more likely $250 or more. So what does the AMD Quad FX line have going for it? Well, to put it bluntly --- not much. In terms of upgrade cost, performance and overall cost of ownership the Intel QX6700 still remains the king of the hill.

The only redeeming aspect is that AMD has announced that the new nForce 680a chipset will be compatible with the future quad-core processors that AMD will release. So, assuming you have a nForce 680a motherboard and a huge 750W or higher power supply, you will be able to upgrade to an octo-core (8 core) system once AMD releases their true quad-core processors some time in 2007.

For nearly every consumer looking to upgrade to a more powerful system this holiday season, the launch of the AMD Quad FX line of CPUs means very little. There is no compelling reason to choose the Quad FX line over an Intel QX6700 or an Intel Core 2 Duo Extreme X6800.

For more information and for test results comparing the AMD Quad FX and the Intel QX6700, check out these articles at PC Perspective and [H]ardOCP.