I have been trying to spec out a new machine lately, which is reminding me all over again how I hate hardware. This time around, the target of my particular hate is AMD CPUs, especially the new AM2 ones, where the performance picture has become so complicated that you need a large chart to understand it.

Choosing CPUs used to be simple: within a given CPU family, the only thing that changed performance was the clock speed, so you could just buy the fastest CPU your budget and desires afforded and be done with it.

Athlons are no longer like that. Within the Athlon 64 X2 AM2 family, there are now three variables: clock speed, L2 cache size per core, and achievable main memory speed (the clock multiplier, as explained by AnandTech). Models with increasing nominal clock speeds zig-zag in the other attributes, to the point where I had to consult the large Wikipedia page of Athlon 64 processors to keep things straight.

(Thank god for Wikipedia. Good luck finding AMD discussing this anywhere you can conveniently find it; I'm not sure they even have a comparison chart of L2 cache sizes on their website.)

Then, once I'd worked all this out, it turns out that the supply of 1MB L2 parts seems to have dried up around here; local computer shops can't even get the Socket 939 versions with 1MB L2 caches, much less the AM2 ones. (Rumour has it that AMD has starved the distributor pipeline in favour of redirecting most of the supply to certain large computer vendors.)

I could try to view the 1MB L2 part drought as a way of simplifying my life, but instead it just irritates me that I can't spec the CPUs I really want.

(I care about the cache size and main memory speed because I tend to think that they dominate performance for the kind of CPU-intensive things I'm likely to do with my machines. Not that I've actually measured this to find out for sure, which makes me some sort of fool.)