Urg! Which CPUs not affected Meltdown/Spectre

None, but patches are being developed, possibly with microcode for Intel arch. AMD/ARM = no clue if they have something similar, but the Spectre impact is not as bad.

Sit tight, turn off non-essential systems, put a blindfold over your eyes for the weekend and pretend nothing will happen until patch Tuesday lol

From a cryptographer's point of view I would politely say thats not correct.

Media reports have been exaggerated, the normal user won't see anything like the 30% slowdown some media sites have been predicting.

0% to 5%, depending on the task, is more likely. So no real reason to replace a CPU. Impact will be on tasks that call the Kernel a lot. Like random seeking on a fast SSD drive.

I normally stay silent if misinterpretations occur.

The lowest risk actually CET 1149 you face by a AMD CPU. Attention! I sad the lowest risk .

https://www.kb.cert.org/vuls/id/584653

Originally this page recommended throwing away the CPU and getting a replacement https://www.kb.cert.org/vuls/id/58465 3">(Posted 04/01/2018).
but has now been updated to suggest simply applying updates https://www.kb.cert.org/vuls/id/58465 3">(Updated 05/01/2018) probably because there are no viable options for replacements. AMD aren't as badly affected but still are.

https://www.kb.cert.org/vuls/id/584653

Originally this page recommended throwing away the CPU and getting a replacement https://www.kb.cert.org/vuls/id/58465 3">(Posted 04/01/2018).
but has now been updated to suggest simply applying updates https://www.kb.cert.org/vuls/id/58465 3">(Updated 05/01/2018) probably because there are no viable options for replacements. AMD aren't as badly affected but still are.

The minimum requirement for working in a CERT would be not to panic while smoking crack, suggesting throwing everything away and buying new stuff. I know of a guy who recommended the same "if the computer has a virus"…

We smoke crack without panic too -)

Intel Atom N family not affected. We have tiny Netbooks in the shelf to help us out N270 (MSI Wind) and N450 (HP Mini 2). And they have an eth port (KRACK overcome).

Small band-aids as for kids.

BIOS, UEFI microcode patches list by manufacturer

https://www.bleepingcomputer.com/news/software/list-of-links-bios-updates-for-the-meltdown-and-spectre-patches/