IBM's 8-core 45nm POWER7 server processor had a wealth of information on the chip, which, at 1.2 billion transistors and 567mm2, is actually quite svelte considering what it offers. The secret is the first use of a special cache technology that IBM has been touting since 2007, but more on that in a moment. POWER7 will come in 4-, 6-, and 8-core varieties, with the default presumably being the 8-core and the lower-core variants being offered to improve yields. Each core features 4-way simultaneous multithreading, which means that the 8-core will support a total of 32 simultaneous threads per socket. POWER7 is designed for multisocket systems that scale up to 32 sockets, which means that a full 32-socket system of 8-core parts would support 1024 threads.
Full Article: Ars