Threadripper vs Epyc (frequencies)

16-core 1950x has base 3400 MHz,
but the 32-core Epyc 7601 is only 2200 MHz
Now for same power, then I would expect Threadripper to have 3100 MHz base.
I realise the Epyc is made to flog all cores 24 hours a day, and is
going to be in pizza box with tiny fans.
So is it that Threadripper is for HEDT, which probably won't max out
eternally, or that cooling is easier with half the dies attached to 1 lid?

wrote:
16-core 1950x has base 3400 MHz,
but the 32-core Epyc 7601 is only 2200 MHz
Now for same power, then I would expect Threadripper to have 3100 MHz base.
I realise the Epyc is made to flog all cores 24 hours a day, and is
going to be in pizza box with tiny fans.
So is it that Threadripper is for HEDT, which probably won't max out
eternally, or that cooling is easier with half the dies attached to 1 lid?

CMOS power is determined by the capacitance being toggled.
The total device power is the sigma (sum) of all
toggling nodes. With double the cores, you would expect
to a zeroth order approximation, the frequency to be
cut in half, for the same run of code. 3400 becomes 1700,
given the limiting conditions of 180W for both devices.

P=FCV^2

The voltage (VCore) used, can be altered as a function
of frequency. When operated at a lower frequency,
the voltage can be adjusted down a bit. That means
the above function is no longer "predictive". You
would need a more refined equation that could
include a correction for voltage savings as a
function of frequency. That's how your 1700MHz
prediction, makes it to 2200MHz.

The 1P versus 2P parts, use up some of their
power-limited power, doing Infinity Fabric
connections. The processor could even be limited
(power limiter cuts in), due to more of the
PCI Express channels being used, or due to
more or less of the 8 DIMM channels (I/O pads) being used.
It all comes out of the 180W limit. (The VCore
of the DIMMs themselves, comes from a separate
budget.)

Other than that, the devices would be considered
to be "equal cooling dilemmas". The coolers
cover the whole lid. We hope the spreader placed
on top of the silicon dice, allows the whole cooler
above to be used.

I won't try to justify all the nuances in the product table.
There are bound to be factors I've missed, so I'm
generally not even curious about what makes the
tables what they are, on modern devices.

Paul