The Athlon 64 X2 chips that will be retired are models 4800+, 4400+, and 4000+ for Socket AM2 and models 4400+ and 4800+ for Socket 939. (AMD will continue to supply the Socket 939 4800+ to select PC makers). All of these CPUs have 1MB of L2 cache for each execution core, and obviously the focus for AMD's product lineup will be shifting toward chips with 512KB of L2 cache per core. The only remaining Socket AM2 processors with 1MB of L2 cache would then be the Athlon 64 FX-62 and any Opteron 100-series processors AMD might release for AM2.
Among single-core chips, the Socket 939 versions of the Athlon 64 with ratings of 4000+, 3700+, 3200+, and 3000+ will get the Kervorkian treatment. Also getting the axe will be the Socket 754-bound Semprons 3300+, 3100+, 2600+, and 2500+. These particular single-core CPU models didn't make the transition from the older sockets to AM2, so their fate is not surprising.
The move to consolidate the Athlon 64 and X2 lines also make some sense, given that AMD has greatly expanded its number of desktop processor offerings in recent weeks by introducing "Energy Efficient" versions of many of its CPUs. We have long believed that clock frequency is more important than the difference between 512KB and 1MB of L2 cache in determining overall performance in the Athlon 64 lineup, and we found that principle to be truer than ever in our Socket AM2 performance testing. Paying a premium for the larger cache didn't make sense. Still, some specs-sensitive soulsincluding PC makers who live for strong feature checklistsmay lament the passing of X2 chips with 1MB of cache per core given the expected arrival of Core 2 Duo processors from Intel with 2MB and 4MB of total shared L2 cache onboard.