Efficacy and noise are also important parameter today. It will be interesting to see such comparisons. It is not obvious that 10900K is optimal if other parameters than raw speed are taking into account. 10900K will be fastest of course but at what cost and how much faster?
Base clock of 10900K is 32% faster than 10900. Turbo all cores only 6% difference and Max boost 2% difference. It is nearly impossible to say according to listed values. I guess long video exports and rendering/raytracing with benefit from higher base clock. For many other usages, there will be little real world difference. If had to chose between a 10-15% slower machine and noise, I would chose silence. At home, I have no AC that can drown the noise from the computer.
Soon we get the heavy criticism from the people that only has speed as important parameter.
Yeah, you poked that particular wasp nest
A lot of factors point towards a light refresh for the 2020 iMac.
a. It was 'ready to ship' in March like the Mac mini but didn't get released - the Mac mini (which got storage doubled for no extra was such a light refresh it's not even officially a 2020 mini). This is obviously before the published launch date of Comet Lake which would struggle in the existing iMac enclosure.
b. Market conditions may have dictated a change of plan for the iMac. We don't know if Corona Virus influenced the forward planning but Apple may see sales fall this year.
c. Comet Lake is a multithreaded workload boost but runs hot when pushed. It's feasible that Apple could use the 27" iMac Pro cooling system but realistically where does that leave the 21.5" model? There's a 23" panel coming that is purportedly cheaper but we don't know where it fits into the Apple lineup - or if it's even intended for an Intel Mac.
d. Remember that Comet Lake is two generations after the majority of the 8th generation Coffee Lake CPUs in the current iMac - and given that certain Kaby Lake 7th generation desktop CPUs have been discontinued you wonder if the Coffee Lake desktop CPUs could be on the way out. Apple could catch up for 2020 with slot-in CPUs for the 9th generation Coffee Lake refresh CPUs which generally allow higher turbos - Apple currently use some CFL-R SKUs in the existing top SKU 27" iMac. Apple could therefore also add the
i7-9700 to the lineup without too much extra engineering work if they felt that more than a storage bump would do.
e. 2021 may bring mini LED backlight which suggests a case redesign will be required to make enclosures thicker for display cooling fans. Why bring it in a year early? Rocket Lake in 2021 would bring PCIe 4.0 and Thunderbolt 4 which is a tangible improvement for Apple. The main advantage of this to Apple is faster SSD performance due to increased SSD bandwidth PCIe x4 lanes would be double the speed - allowing
reads of 6500Mb/s and write of 5000Mb/s if you believe the Samsung 980Pro figures). It would also allow a total of 20 PCIe lanes which would in theory allow a more fully featured Mac with dGPU, 4 Thunderbolt ports, and 10 Gigabit ethernet.
