TODO merge in my notes from corey, CS152

TODO fused multiply add (FMA)

misc notes

• harvard architecture: separate instr & data mem
• x87: the FPU

SSE

• has ssqrt and a much faster rsqrt

ARM

• invents designs; licenses to actual mfr's
• reasonable perf, good price/perf, amazing power/perf
  • no multicore, no >2gb ram
• pushed by dga (FAWN), james hamilton

intel atom

• good low-power chip but currently no 64-bit mem or ECC

RAM

• frequency, bandwidth: each xfer ships 8 bytes
  • eg ddr3-1333 (pc3-10600): 1333 MHz * 8 bytes/xfer = 10.6 GB/s
• ddr: data per xfer; ddr = 2x, ddr2 = 4x, ddr3 = 8x
  • eg ddr3-1333 (pc3-10600): already accounts ddr3
• channels: width btwn cpu and ram
  • eg dual channel ddr3-1333 (pc3-10600): 2*10600=21200 GB/s
• registered ram: buffered; higher capacity but lower latency
• rank: independently accessible 64-bit area of the memory (don't understand)
• misc terms: ecc, capacity