Re:Ryzen is for Programmers
by paulmd on Tuesday May 02, 2017 @01:13PM
(#14248299)
The HEDT chips have very low stock clocks but they overclock really well.
Broadwell is kind of an exception here since it clocks so poorly both in the small-chip and HEDT form. But for example, 4.7 GHz is a good OC for Small Haswell and the Haswell-E HEDT chips will usually go to at least 4.5 GHz.
(of course the major caveat here is power - a highly OC'd 8-10 core chip can easily pull 200-250 watts package TDP on a normal workload, 300+ watts as measured at the wall. For an AVX-heavy workload like Prime95, add another 100 watts package TDP.)
So overall the penalty for using HEDT chips is nowhere near as big as you are implying here. It's something on the order of 4% loss of single-thread performance to go from 4-core to 8-10 cores. It just doesn't come that way out of the box - largely because anyone who buys a 10-core gaming chip for $1700 knows exactly how to do all this.
The bigger problem is that the HEDT chips are 2 generations behind the smaller chips. Broadwell vs Broadwell-E, the numbers look fine, but Kabylake has some IPC improvements and clocks significantly higher than Broadwell does.
This is one of those things that actually can be blamed on "Intel being lazy because they have no real competition". They could certainly push the HEDT chips out a little faster instead of waiting to work out all the bugs in the smaller chips, it would just be a bit riskier for them.
Broadwell is kind of an exception here since it clocks so poorly both in the small-chip and HEDT form. But for example, 4.7 GHz is a good OC for Small Haswell and the Haswell-E HEDT chips will usually go to at least 4.5 GHz.
(of course the major caveat here is power - a highly OC'd 8-10 core chip can easily pull 200-250 watts package TDP on a normal workload, 300+ watts as measured at the wall. For an AVX-heavy workload like Prime95, add another 100 watts package TDP.)
So overall the penalty for using HEDT chips is nowhere near as big as you are implying here. It's something on the order of 4% loss of single-thread performance to go from 4-core to 8-10 cores. It just doesn't come that way out of the box - largely because anyone who buys a 10-core gaming chip for $1700 knows exactly how to do all this.
The bigger problem is that the HEDT chips are 2 generations behind the smaller chips. Broadwell vs Broadwell-E, the numbers look fine, but Kabylake has some IPC improvements and clocks significantly higher than Broadwell does.
This is one of those things that actually can be blamed on "Intel being lazy because they have no real competition". They could certainly push the HEDT chips out a little faster instead of waiting to work out all the bugs in the smaller chips, it would just be a bit riskier for them.