Problem the cores are not recognized


New Member
Jun 30, 2023
Install proxmox pve-manager/7.4-15/a5d2a31e, on a computer with an Intel(R) Core(TM) i3-10105 processor, and it only recognizes one core, not the 4 that it should.

1 x Intel(R) Core(TM) i3-10105 CPU @ 3.70GHz (1 Socket)

kernel version
Linux 5.15.108-1-pve #1 SMP PVE 5.15.108-1 (2023-06-17T09:41Z)

PVE Manager Version

If all cores are enabled from the bios, also try setting GRUB_CMDLINE_LINUX="maxcpus=4" in grub.

lscpu output

Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
Address sizes: 39-bit physical, 48-bit virtual
CPU(s): 1
Online CPU(s) list: 0
Thread(s) per core: 1
Core(s) per socket: 1
Socket(s): 1
NUMA node(s): 1
Vendor ID: GenuineIntel
CPU family: 6
Model: 165
Model name: Intel(R) Core(TM) i3-10105 CPU @ 3.70GHz
Stepping: 3
CPU MHz: 4200.003
CPU max MHz: 4400.0000
CPU min MHz: 800.0000
BogoMIPS: 7399.70
Virtualization: VT-x
L1d cache: 32 KiB
L1i cache: 32 KiB
L2 cache: 256 KiB
L3 cache: 6 MiB
NUMA node0 CPU(s): 0
Vulnerability Itlb multihit: KVM: Mitigation: Split huge pages
Vulnerability L1tf: Not affected
Vulnerability Mds: Not affected
Vulnerability Meltdown: Not affected
Vulnerability Mmio stale data: Vulnerable: Clear CPU buffers attempted, no microcode; SMT disabled
Vulnerability Redebled: Mitigation; Enhanced IBRS
Vulnerability Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl and seccomp
Vulnerability Specter v1: Mitigation; usercopy/swapgs barriers and __user pointer sanitization
Vulnerability Specter v2: Mitigation; Enhanced IBRS, IBPB conditional, RSB filling, PBRSB-eIBRS
SW sequence
Vulnerability Srbds: Vulnerable: No microcode
Vulnerability Tsx async abort: Not affected
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse
36 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 xtopo
logy nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl
vmx est 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 epb invpcid_single ssbd ibrs ibpb stibp ib
rs_enhanced tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc
_adjust bmi1 avx2 smep bmi2 erms invpcid mpx rdseed adx smap clflusho
pt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hw
p hwp_notify hwp_act_window hwp_epp md_clear flush_l1d arch_capabilit

CPU Specifications Number of cores 4
Number of threads 8

What I can do?
Last edited:


The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get yours easily in our online shop.

Buy now!