<Yeah... I figured that you had to have a pretty advanced design (with an <accompaning fab, although I don't really know about this stuff, it seemed <like 1 micron was the magic number for on chip caches). I've always liked <large caches on everything: 512K on a hard drive, a meg on a motherboard, The key was getting a fab process that could support the extra logic and the added gates to form the cache memory and cache control. Also caching requires a lot more smarts that are added to the basic cpu. It represents a great increase in complexity, total number of logic on die and potentially power consumption. Those are all parameters to be balanced. Allison