'When the Raspberry Pi 400 (a keyboard form-factor single board
computer) was released last week, the company hinted at overclocking.
Testing has now shown that the heat spreader used in that design does
an excellent job. The chip was already clocked at 1.8 GHz, versus the
stock 1.5 GHz in the original Raspberry Pi 4 Model B board. But it can
be safely overclocked to 2.15 GHz, as can the Compute Module 4 with an
adequate heat sink.
At 2.0 GHz, the Pi 400 got up above 60 C and showed signs of
continuing to warm up even after 50 minutes, but it was nowhere near
throttling. So I tried 2.2 GHz, at which speed the CPU refused to boot
entirely. Backing down to 2.15 GHz, it ran just fine, so I left it for
three hours. It settled in at a cozy 62.5 C, which is warm, but well
I ran the CM4 with the larger heatsink at 1.8 GHz to give some basis
for comparison to the cheap heatsinks. What a big difference a big
hunk of aluminum makes! It settled in at a comfortable 68 C or so.
Even pushing it up to 2.15 GHz and leaving it for a couple hours, it
stayed just a hair below 70C (158F) -- a safe margin on the throttling
threshold -- and only a few degrees warmer than that huge heat
spreader in the Pi 400.'
-- source: https://hardware.slashdot.org/story/20/11/11/182203
Dept. of Computer Science
University of Waikato, NZ
+64 (7) 577-5304