Tyan K8WE (S2895)
For our AMD Opteron tests we needed one more mainboard that could be suitable for a high-performance workstation platform, i.e. could be similar to Supermicro X6DA3-G2 in features but supported Socket 940 processors. It was an easy task to find a mainboard like that. Although quite a few mainboard manufacturers are offering mainboard solutions like that, we fell for the Tyan K8WE (S2895), which has been receiving a lot of positive response from the users lately.
This mainboard is based on NVIDIA nForce Professional, which is actually not surprising at all. One of the major criteria defining a platform as a workstation solution, and not a server one is a graphics bus that allows using high-performance graphics cards. As of today, there is only one chipset family for dual-processor AMD Opteron systems supporting PCI Express x16 bus – NVIDIA nForce Professional (unfortunately, we cannot regard ServerWorks HT-2000 chipset as an alternative to NVIDIA’s solution here, because of its extremely limited availability).
NVIDIA nForce Professional chipset consists of two chips, which can be used together or separately in the end-systems. Tyan K8WE (S2895) mainboard features both these chips. Here I would like to stress that different combinations of nForce Professional chips affect only the peripheral features of the mainboard and do not matter for the CPU and memory support. The main reason for that is the fact that in dual-processor systems built with AMD Opteron CPUs, the two processors communicate with one another via the direct HyperTransport bus working at 1GHz and featuring 8GB/s data transfer rate, and the memory support is provided by the memory controllers integrated into the CPUs.
Therefore, the list of basic features of the Tyan K8WE (S2895) mainboard is primarily determined by the Opteron processors and not by the system core logic. This mainboard is equipped with two Sockets 940 that can accommodate any CPUs from this processor family, including single-core and dual-core models. Here I have to stress that the release of dual-core processors didn’t require any changes to be made to the mainboard design on the hardware level. Since the dual-core Opteron processors are pin-to-pin compatible with their single-core brothers and do not require any additional power, the only thing they need to be supported on the existing platforms is the BIOS update.
To the right of each CPU socket there are four DIMM slots. Opteron processors feature an integrated dual-channel memory controller requiring Registered DDR400 SDRAM memory modules (or slower). Note that even though the memory subsystem in the dual-processor Opteron system is split into two sub-systems for each of the CPUs, it is still functioning as a single address space thanks to NUMA technology. So, if you install at least two Registered DDR400 SDRAM memory modules into your Tyan K8WE (S2895) based system, you can calculate the peak memory bandwidth keeping in mind that it can work in four-channel mode. As for the maximum supported memory capacity, it can be determined basing on the maximum capacity of the Registered memory modules available in the today’s market. As of today, the maximum memory capacity for the Registered DDR SDRAM DIMMs is 2GB per modules, so Tyan K8WE (S2895) can theoretically accommodate up to 16GB of memory.