The first samples of 21264B (EV68C) were delivered in the beginning of 2000. They were produced by IBM using 0.18µ CMOS8 copper compound process. Despite the absence of any architectural differences, the promising technology allowed raising the core frequencies right to 1250MHz. In 2001, Samsung was able to manufacture in series 21264B (EV68A) using their own 0.18µ aluminum process, which allowed reducing the die size to 125mm² and the voltage to 1.7V. As a result, they managed to fit the core frequencies between 750MHz and 940MHz (TDP approx. from 60W to 75W).

Different sources mention 21264C and 21264D, codenamed EV68CB and EV68DC respectively, manufactured by IBM with the same technology as EV68C, and running at the same frequencies, so they could be considered their minor modifications. The only noticeable difference was a new form-factor, "pinless" CLGA-675 (Ceramic Land Grid Array) used instead of PGA-587.

There were 2 chipsets designed for 21264 series of processors: DEC Tsunami (21272; also known as Typhoon) and AMD Irongate (AMD-751). In fact, there could have been much more chipsets since both, 21264 and Athlon, used almost the same system bus (AMD licensed it from DEC).

DEC Tsunami was a highly scalable chipset. It could be used to build single-processor, as well as dual-processor and quad-processor systems, with the memory bus width from 128 to 512 bits (registered SDRAM with ECC, 83MHz), and supporting from one to several PCI buses (64-bit, 33MHz). They managed to achieve this flexibility by splitting the chipset into individual components: system bus controllers (C-chips, one per processor), memory bus controllers (D-chips, one per every 64 bits of bus width), and PCI bus controllers (P-chips, one per bus). So, no wonder, that some systems (for example, AlphaPC 264DP) had chipsets consisting of 12 separate chips...

Although AMD Irongate was developed to serve as a North Bridge for Athlon-based mainboards, it was used in some Alpha mainboards (for example, in UP1000 and UP1100). Being a single-chip solution, it cost much less than DEC Tsunami, and consumed much less power. But, it wasn't the best solution for 21264, because lacked multi-processor support and had a narrow memory path (64-bit, unbuffered SDRAM with ECC, 100MHz). Nevertheless, Irongate was the first chipset for Alpha to feature AGP bus support. And the last.