The Opteron Processor
Before we get into talking about the chipset, we will take a moment to have a look at the processor which will be accompanying our test motherboard today.
The AMD Opteron is the latest processor to hit the market and carries the long awaited 64-bit architecture to the retail market. While we have seen Intel release a 64-bit processor to the market in the shape of the Itanium and Itanium 2 some time ago, it was one product that the end-user would not consider purchasing due to its high price tag and lack of chipset support.
The Opteron comes with a massive 940 pin count which is the largest of any processor implementing the PGA format. PGA or Pin Grid Array can be separated into two parts: the first being Pin, which in this case is the small metal pins we see coming from the bottom of the processor and the other is the Grid Array. The Grid Array is the formation the pins are in, which here is a 940 pin formation. Together we have the highest pin count currently on the market for this kind of technology. The Opteron processor also carries a huge 1MB of L2 cache to help when it comes to processor-hungry applications. The Opteron also has three Hyper Transport buses which we will look into more in just a moment.
What else AMD has in store for 64-bit
While we are on the subject of AMD processors, we may as well have a quick look at what else AMD have in store for the 64-bit market.
The cheapest of AMD's 64-bit line will be known as the Athlon 64 and will most likely be launched next month in Taiwan at Computex 2003. The Athlon 64 will be the entry level 64-bit processor and the mainstream product with a pin count of 754 replacing Athlon XP. Athlon 64 has the smallest amount cache out of the group with only 512k and will only support Single Channel DDR and one Hyper Transport Bridge meaning it is not SMP-capable.
The other processor which will be making an introduction, which seems to be confusing a lot of people, is Athlon FX or Athlon 64 FX. The Athlon FX will be the enthusiast processor, according to speculation currently floating around. Consisting of 1MB cache and three Hyper Transport buses, the only difference between it and the Opteron is support for SMP. The Athlon FX will consist of 939 pins; the pin that is missing is the one that gives it the ability to run Dual Processor mode.
Hyper Transport Buses
As we just mentioned, the Opteron and the Athlon FX will consist of multiple HT (Hyper Transport) buses, while the cheaper mainstream Athlon 64 will only have one.
One of the buses goes to your peripherals (your AGP slot, PCI slot, etc). This is the only one on the Athlon 64. The second bus is used between processor one and two, while the third bus is used when running quad processor systems.
While Athlon FX and Opteron have support for all three, the Athlon 64 and Athlon FX only use one. The Opteron only uses two - one for the peripherals and one that contacts the other processor for SMP mode operations. We may end up seeing an Opteron processor with three buses for quad processor setups, but we haven't heard anything yet.
As far as we can tell and from what we have been told, the only difference between Athlon 64 and Athlon FX will be double the cache and the Dual Channel DDR controller built into the Athlon FX instead of the Single Channel option with the Athlon 64.
Now you've been brought up-to-speed with everything AMD64, let's continue...