Introduction
Corsair XMS 3200 (DDR-400) CAS2 Memory Review
Introduction
Do you remember the fanfare that greeted the introduction of DDR (double data rate) memory approximately 18 months ago ?. I certainly do. It was reckoned to be a major enhancement towards the goal of a faster subsystem. At that time, PC1600 was prevalent, with only a few PC2100 modules popping up here and there.
The birth of the Pentium 4, with its quad-pumped front side bus (FSB), saw the need for faster versions of DDR memory. After all, the present Northwood B processor, running off a quad-pumped 133MHz FSB, can utilise up to 4.26GB/s of potential bandwidth. The Athlon XP, however, with its double-pumped FSB, is still only able to harness 2.13GB/s of memory bandwidth. Newer, upcoming motherboards for the Socket A platform should see that change to some degree. There's been considerable talk about the Athlon moving on to a faster 166MHz FSB.
The Pentium 4 has seen a number of recent chipsets that officially support DDR333 memory. We now see SiS' 648 chipset and VIA's P4X400 provide indirect support for super-fast DDR-400 memory. I expect this trend to continue unabated over the coming months.
A number of today's applications are memory-intensive in nature, boosting the system's memory speed has empirically proven to increase system performance tangibly. Our benchmarks here at Hexus have been testament to that. Just before we look at the memory in for review today, we'll just recap on the modules that are currently available.
PC1600 - 1.600GB/s bandwidth (8 x 100 x 2), runs at DDR-200
PC2100 - 2.128GB/s bandwidth (8 x 133 x 2), runs at DDR-266
PC2400 - 2.400GB/s bandwidth (8 x 150 x 2), runs at DDR-300
PC2700 - 2.656GB/s bandwidth (8 x 166 x 2), runs at DDR-333
PC3200 - 3.200GB/s bandwidth (8 x 200 x 2), runs at DDR-400
RAMBUS PC800 - 3.200GB/s bandwidth (2-bytes x 800Mhz x 2 RIMMS)
RAMBUS PC1066 - 4.26GB/s bandwidth (2-bytes x 1066MHz x 2 RIMMS)
Memory is not only differentiated by the speed it operates at, it can also be differentiated by the timings that it uses to run at various speeds. A number of memory timings can be manipulated in most motherboards BIOS'. The lower the timings (numerically), the better the performance. CAS (Column Access Strobe) latency usually has the most impact on performance. A CAS latency of 2 clocks is what we ideally look for in our memory. The problem, however, is one of validating memory at this stringent timing. The need to produce high-quality modules is an absolute must as signal integrity is easily compromised at high frequencies.
That leads me nicely into the memory in review for today. I'll be casting my eye over some super-fast memory from Corsair Micro. Corsair is a name synonymous with high-performance memory. They're particularly noted for providing memory that meets and often exceeds the fastest standards currently in place. Corsair employ a six-layer, impedance-controlled PCBs to ensure that quality standard are kept high.
Speaking of standards, JEDEC, the governing body that administers standards for new speeds of memory, have yet to ratify a standard faster than PC2700 memory. Therefore, faster memory is solely released to satiate the needs of new chipsets that unofficially support faster speeds, or those who are looking to maximise their system bandwidth.
So, we know there is a demand for super-fast memory, the question is just how well can Corsair fill it with their latest and greatest modules ?. Read on and find out.