3 ms·

Plus lower base and boost clocks

• rbanffy 7y ago
  That is somewhat offset by twice as much memory bandwidth. Every L3 miss on a 3990X is twice as expensive as it's on the 7702P
  • dragontamer 7y ago
    And the EPYC uses higher latency RDIMMs and LRDIMM RAM. Traditionally, server RAM (RDIMM or LRDIMMs) is 50ns+ slower than consumer UDIMMs. Video games and pointer-chasing care more about that latency figure than bandwidth. I'm sure there are bandwidth-bound tasks, but any latency-bound task would prefer highly-clocked, over-volted (1.35V) DDR4 UDIMMs at 3200 MT/s CAS16 or faster. Server RDIMMs are naturally slower, due to the register (and LRDIMMs are probably even slower). RDIMMs and LRDIMMs are designed for capacity more so than latency: you can have 1TB of LRDIMMs RAM on one machine but all the RAM runs slightly slower (3200MT/s maybe CAS22 or slower) as a result.
    • tuananh 7y ago
      > 50ns+ slower than consumer UDIMMs. is that like twice as slow?