Used Cores / Threads CPU E3-1230 V2

Hello List,

I use a Xeon(R) CPU E3-1230 V2 on bios0: Supermicro X9SCL/X9SCM
This is a 4 Core 8 Threads cpu.

In dmesg, cpu0 to cpu7 are displayed as follows:
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: Intel(R) Xeon(R) CPU E3-1230 V2 @ 3.30GHz, 3300.47 MHz,
06-3a-09
cpu0: FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,
... MELTDOWN
cpu0: 256KB 64b/line 8-way L2 cache
cpu0: apic clock running at 100MHz
cpu0: mwait min=64, max=64, C-substates=0.2.1.1, IBE
cpu at mainbus0: not configured

Now I'm a bit confused about the views in top and htop.

top shows me cpu0 to cpu3.

htop shows me 1 to 8, but 5 to 8 is shown as "offline"

It is (uname -a): OpenBSD user@host 7.1 GENERIC.MP#461 amd64
and some kernels before.

Now my question, in "top" only the physical cores are displayed.
In "htop" all that are also shown in dmesg.

But why are the cpu4 to cpu8 displayed as "offline".
Is really only cpu0 to cpu3 used and not cpu4 to cpu7,
how can I interpret that correctly?

Thank you for the clarification in advance.
/Heiko