AMD Ryzen 7 PRO 7735U: 8 instead of 16 CPUs?

From: Dirk Gouders
Date: Wed Apr 09 2025 - 06:50:36 EST


I got new hardware and after setting up everything, I was wondering why
I don't see the expected 16 CPUs in top(1) or /proc/cpuinfo...

>From the AMD website [1] I read:
------------------------------------------------------------------------
Name AMD Ryzen™ 7 PRO 7735U
...
Architecture Zen 3+
# of CPU Cores 8
...
# of Threads 16
------------------------------------------------------------------------

But lscpu(1) shows me:
------------------------------------------------------------------------
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Address sizes: 48 bits physical, 48 bits virtual
Byte Order: Little Endian
CPU(s): 8
On-line CPU(s) list: 0-7
Vendor ID: AuthenticAMD
Model name: AMD Ryzen 7 Pro 7735U with Radeon Graphics
CPU family: 25
Model: 68
Thread(s) per core: 2
Core(s) per socket: 4
Socket(s): 1

------------------------------------------------------------------------

Then, I booted a BSD livesystem (NomadBSD), looked at dmesg(1):
------------------------------------------------------------------------
# dmesg | grep SMP
FreeBSD/SMP: Multiprocessor System Detected: 16 CPUs
FreeBSD/SMP: 1 package(s) x 8 core(s) x 2 hardware threads
------------------------------------------------------------------------

And I installed it's lscpu(1) and that reports:
------------------------------------------------------------------------
Architecture: amd64
Byte Order: Little Endian
Total CPU(s): 16
Thread(s) per core: 2
Core(s) per socket: 8
Socket(s): 1
Vendor: AuthenticAMD
CPU family: 25
Model: 68
Model name: AMD Ryzen 7 Pro 7735U with Radeon Graphics
------------------------------------------------------------------------

Do I misunderstand something from the above?

Best regards,

Dirk

[1] https://www.amd.com/en/products/processors/laptop/ryzen-pro/7000-series/amd-ryzen-7-pro-7735u.html