Monday, October 22, 2001

Fiberglass

Until recently, all Athlon CPUs have used a ceramic base. Now, however, with the introduction of the Athlon XP, AMD has made the switch to fiberglass - the same material used to manufacture motherboards. So it's out with the PPGA (Plastic Pin Grid Array) interface, and in with OPGA (Organic Pin Grid Array). This change has come about primarily as a cost saving measure - its simply cheaper to work with fiberglass than ceramic - and in part due to fiberglass' lower impedance. Impedance is essentially a measurement of a circuit's opposition to the passage of electrical alternative current (AC) , while resistance is the opposition to the passage of electrical direct current (DC).

Power consumption and dissipation

Since its inception, the Athlon-family has long been known not only for its tremendous processing power, but also for the tremendous amount of heat its members generate. Now, while this may not be a problem that has been totally rectified with the Athlon XP, it has certainly been ameliorated. So, with the XP's required voltage still set at 1.75v, the chip's actual power consumption has been reduced by 20%. And, with a reduction in power consumption, comes a similar reduction in heat dissipation - which will certainly come as a relief to users.

The thermal diode

Up until now, AMD has seen fit to include a thermal diode as part of its Athlon processor. Now though, the XP comes equipped with a diode all its own, which will permit XP users with the right motherboard to measure the operating temperature of their CPUs. And, as you might expect, with the right BIOS or software, such systems will even be capable of automatic shutdowns in the event of temperatures over and above a pre-selected limit. While this may not seem like a great leap forward compared to Intel CPUs, which are already capable of auto-self-protection in such cases, it is certainly a much awaited step in the right direction. However, bear in mind that a good part of actual socket A motherboards are relying on their own thermal diode to sense the CPU temperature and that it'll take quite some time before the newly designed motherboards will begin to use the XP internal thermal diode. An example of this is the internal thermal diode of Intel's processors that is implemented for years whilst motherboards designs are only beginning to use it...

Support for SSE instructions

52 new instructions have also taken up house in the Athlon XP's arsenal, and, even though they'll only be of use to apps that have been programmed to take advantage of them, they represent quite a milestone for the Athlon. Up until now, AMD's Athlon offerings have only supported 3DNow! instructions for SIMD operations. The Athlon XP continues to support for 3DNow!, but now adds to it support for SSE instructions, an addition that should prove welcome among most users. In fact, rumors have already started that imply that a future version of the XP will not only support SSE, but also Intel's latest set of SIMD instructions - SSE2.

Approved motherboards

Below is a link to a current list of motherboards that have been approved by AMD for use with the AMD Athlon XP:

AMD approved motherboards

Pricing

Below is a list of the current prices (as of the time of writing) for the Athlon XP, as expressed in American dollars: