CPU utilizing only one thread; all other cores there yet no utilization

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Per title, only one thread of my cpu is being used in cpu stress tests and elsewhere. s-tui test imgur: xXuRdmd.png
Other tests such as stress --cpu net the same results in htop. Using Intel i9-10850K (18) @ 5.200GHz, Manjaro KDE, and issue is able to be replicated across kernels 5.10-14.
Output of lscpu, all cpus online:

Architecture:           x86_64
  CPU op-mode(s):       32-bit, 64-bit
  Address sizes:        39 bits physical, 48 bits virtual
  Byte Order:           Little Endian
CPU(s):                 18
  On-line CPU(s) list:  0-17
Vendor ID:              GenuineIntel
  Model name:           Intel(R) Core(TM) i9-10850K CPU @ 3.60GHz
    CPU family:         6
    Model:              165
    Thread(s) per core: 2
    Core(s) per socket: 9
    Socket(s):          1
    Stepping:           5
    CPU max MHz:        5200.0000
    CPU min MHz:        800.0000
    BogoMIPS:           7202.00
    Flags:              fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl e
                        st tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault invpcid_single ssbd ibrs ibpb stibp ibrs_enhanced fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid mpx rdseed adx s
                        map clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify hwp_act_window hwp_epp pku ospke md_clear flush_l1d arch_capabilities
Caches (sum of all):    
  L1d:                  288 KiB (9 instances)
  L1i:                  288 KiB (9 instances)
  L2:                   2.3 MiB (9 instances)
  L3:                   20 MiB (1 instance)
NUMA:                   
  NUMA node(s):         1
  NUMA node0 CPU(s):    0-17
Vulnerabilities:        
  Itlb multihit:        KVM: Mitigation: VMX unsupported
  L1tf:                 Not affected
  Mds:                  Not affected
  Meltdown:             Not affected
  Spec store bypass:    Mitigation; Speculative Store Bypass disabled via prctl and seccomp
  Spectre v1:           Mitigation; usercopy/swapgs barriers and __user pointer sanitization
  Spectre v2:           Mitigation; Enhanced IBRS, IBPB conditional, RSB filling
  Srbds:                Not affected
  Tsx async abort:      Not affected

grub config is the same, nothing limiting cpus

Not really sure where to start with this problem, since I haven’t found anyone with this specific issue. Is it a hardware problem? Other cores very occasionally turn on for a few percent of utilization so they aren’t dysfunctional. I’ve tried editing some bios such as turning off overclocking, virtualization, and hyperthreading or anything else that could possibly affect this but no luck. Is it a problem with SMP in the kernel?

Thank you for reading through, I hope you can help.

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