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by helpbygrace 4810 days ago
If you are correct for the first clause(8 Flops/MHz), 45GHz of Ivy Bridge core has 360k Flops (8 Flops/MHz * 45GHz ==> 8 Flops * 45k).
2 comments

8 double-precision flops/cycle/core is the correct figure for Ivy Bridge and Sandy Bridge. With Haswell adding FMA, that figure doubles again(!)
Hum, no. Sandy/Ivy Bridge can only execute 4 double-precision instructions per cycle per core, in the form of two SSE instructions per cycle (one instruction doing adds, the other doing muls, executed by different units).

Doing 8 double-precision instructions per cycle would translate to either four 128-bit SSE instructions, or two 256-bit AVX instructions per cycle, which is not possible (unless I did not keep track of the latest AVX capabilities).

It should read 8 FLOPS per cycle double precision. So a 3 GHz 4 core Ivy Bridge processor could theoretically peak at 96 GFLOPS double precision, 192 GFLOPS single precision.