My guess is that this is a VC133 256MB stick of VCM-SDRAM based on the chipset support list. Do you want it? Well, I wouldn't replace my current memory with VCM-SDRAM, but if you are buying a new system, it's worth considering. Virtual Channel Memory essentially adds a small cache to SDRAM. VC133 SDRAM will result in up to a 10% speed-up in an ideal situation over comparable PC133 memory, but it's more like 3-4% in real life.