Intel Launches $699 Core I9-13900KS, the First 6 GHz CPU: Available Now

Post by eightysixfour » Thu, Jan 12, 2023, 10:08 PM UTC

daveguy wrote: post #92

TheRealPomax wrote: post #83

Earlier quoted context omitted.

Sort of but also not really: performance per watt is not the complete measure of improvement, you need to look at "performance, per watt, per wasted watt": If your high performance CPU uses 75W just to stay powered on, then its almost certainly not an improvement over a slower CPU that burns through less energy just to power the cores at all. For example, let's contrast the 13700k to the ancient 7920X. The 13700K ben…

I'm not sure this is the right way to look at it. If you take it to an extreme the flaw is apparent. Let's say "bogomips" is the name of a real world accurate benchmark. If a CPU at full performance gives 100 bogomips at 2 watts and idles at 1 watt by your metric the score is 50. On the other hand, if a CPU at full performance gives 200 bogomips at 2 watts and idles at a small fraction under 2 watts, your metric also…

Post by arcticbull » Thu, Jan 12, 2023, 11:44 PM UTC

eightysixfour wrote: post #93

speculativename wrote: post #86

Earlier quoted context omitted.

Agreed, but just shouting out the brand new AMD 7900 non-x. 12 cores with a 65w tdp is pretty cool, if I was making a power efficient workstation or itx build right now that's almost certainly what I would use.

The non-x products make it clear that the “x” products are just way out of line on the performance/power scale.

Post by credit_guy » Thu, Jan 12, 2023, 11:47 PM UTC

eightysixfour wrote: post #101

daveguy wrote: post #92

Earlier quoted context omitted.

I'm not sure this is the right way to look at it. If you take it to an extreme the flaw is apparent. Let's say "bogomips" is the name of a real world accurate benchmark. If a CPU at full performance gives 100 bogomips at 2 watts and idles at 1 watt by your metric the score is 50. On the other hand, if a CPU at full performance gives 200 bogomips at 2 watts and idles at a small fraction under 2 watts, your metric also…

I’m not these metrics are getting to the root problem: The 13900KS boosts to 6ghz at 320w. The 13900K boosts to 5.8ghz at 253w. That’s a 3.4% increase in clock speed at the cost of a 26.5% increase in power. The marginal power cost for the frequency increase is way out of line.

  "but the extra 'S' in the name denotes that this is premium-binned silicon that hits 6 GHz on two cores — 200 MHz faster than the 12900K"

Post by toast0 » Thu, Jan 12, 2023, 11:51 PM UTC

helf wrote: post #78

Dalewyn wrote: post #66

Earlier quoted context omitted.

My take is this: If I see 90%+ CPU load (being "efficient"), I need a bigger CPU. If I hardly see any CPU load, I am being effective. Ergo, the biggest CPU I can afford is the best choice. I don't consider unused CPU power as waste, I see it as relief from worrying about capping out.

90%+ CPU load at... what frequency? That rule doesn't make a lot of sense unless you are meaning "90%+ load while sustaining maximum core clocks"

Post by devnullbrain » Thu, Jan 12, 2023, 11:54 PM UTC

omni wrote: post #81

dijit wrote: post #77

Earlier quoted context omitted.

> It seems like you definitely need at least an AIO watercooler There is another problem with watercooling, which is that once the water warms up (which it will under sustained loads) your CPU temperature will begin to climb. Then it becomes a game of "do I have thermal mass enough to run my job before throttling", and often it can be the case that radiators are unable to effectively cool down the CPU; but the additi…

> sometimes giving the appearance of better cooling when in actuality your system will throttle after 10 minutes of work. If it throttles after 10 minutes instead of after 20 seconds, that is in fact better cooling. The higher thermal mass is one of the major benefits of water cooling over air cooling for this reason.