Is there any way to check if my CPU is working without errors? There are CPUburn and MPrime to stress-test the CPU and check for temperatures and throttling, but is there any program that will actually check for errors without necessarily stressing out the CPU? (E.g. compare multiple calculations and log silent errors, or similar?)
I suggest trying stress-ng with the cpu stressor and verify mode enabled:
sudo apt-get install stress-ng stress-ng --cpu 0 --verify --verbose --timeout 5m
The above with run the CPU stress test with verification enabled on all CPUs for 5 minutes. If there is something broken, the verify mode may just detected it.
The CPU stressor will exercise the following CPU stress test methods: ackermann bitops callfunc cdouble cfloat clongdouble correlate crc16 decimal32 decimal64 decimal128 dither djb2a double euler explog fft factorial fibonacci float fnv1a gamma gcd gray hamming hanoi hyperbolic idct int128 int64 int32 int16 int8 int128float int128double int128longdouble int128decimal32 int128decimal64 int128decimal128 int64float int64double int64longdouble int32float int32double int32longdouble jenkin jmp ln2 longdouble loop matrixprod nsqrt omega parity phi pi pjw prime psi queens rand rand48 rgb sdbm sieve stats sqrt trig union zeta.
Consult the stress-ng manual using
man stress-ng for the full details of these cpu stressors.