CPU Upgrade Optiplex 7020 SFF

Here is the technical guidebook for OptiPlex 7020 and i7-4790K was not a supported configuration by Dell.  Although, users validated systems here and here, provided that the i7-4790K would work with the 7020.

Note that the MT chassis will provide better airflow than an SFF.  Weight your option between thermal management and the benefits a K processor provides, if any.

Thank you very much for your answer. I could not find this documentation.

I'll ask again. The i7-4790 has a TDP of 84W and the i7-4790K has a TDP of 88W. Do you think the 4W will be a big problem for heat dissipation?
In terms of performance, the i7-4790K is maybe around 11-17% better than the i7-4790, according to various sites.

answering the q for chino and hope it is in agreement, that 4 w difference is minimal.  the -k cpu 4790k is a better pinned cpu in silicon lottery.  the peformance you see is average benchmark.  what you will actually get is a different experience for different user.

The i7-4790K *will* run on a 7020 SFF (Disclosure-I tested on my 3020 SFF, fitted with the XE-2 fan/heatsink J9G15), but...this racehorse of a CPU runs HOT. When I tried, it felt like the first test launch of Starship- a wild WILD ride to just keep temps under 100 C. Besides, the Optiplex MBD will let not you overclock the CPU, which is part of the reason behind the K. I feel you'll be better served with the i7-4790. It is well matched to J9G15, and you'll still get Hyperthreading. Some applications will benefit from 4 extra virtual cores.