My motherboard provides 4x USB 3.2 Gen1 ports for rear I/O and another 2x USB 3.2 Gen1 ports for front I/O (through the header), but my chipset only supports 2x USB 3.2 Gen1 ports. Where is the support for the other ports coming from?
| Motherboard | Wikipedia |
|---|---|
The motherboard is an ASRock B450M Steel Legend
Nah SATA is built into the chipset. That second x16 is actually only electrically x4 in an x16 form factor, and there’s that x1 slot, adding up to 5 lanes in total. The first x16 and first nvme slot (x4) are connected to the CPU directly (which IIRC most have 20 lanes on AM4, but not always).
Oh, that makes sense, thanks
My CPU (1600 AF) only has 16 lanes, but I have a graphics card and an NVMe SSD and both seem to be getting all the lanes. I wonder what’s going on here
07:00.0 VGA compatible controller: NVIDIA Corporation TU116 [GeForce GTX 1650 SUPER] (rev a1) (prog-if 00 [VGA controller]) Subsystem: Micro-Star International Co., Ltd. [MSI] TU116 [GeForce GTX 1650 SUPER] [...] LnkCap: Port #0, Speed 8GT/s, Width x16, ASPM L0s L1, Exit Latency L0s <1us, L1 <4us ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp+ LnkCtl: ASPM Disabled; RCB 64 bytes, Disabled- CommClk+ ExtSynch- ClockPM+ AutWidDis- BWInt- AutBWInt- LnkSta: Speed 8GT/s (ok), Width x16 (ok) TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
01:00.0 Non-Volatile memory controller: Silicon Motion, Inc. SM2262/SM2262EN SSD Controller (rev 03) (prog-if 02 [NVM Express]) Subsystem: Silicon Motion, Inc. SM2262/SM2262EN SSD Controller [...] LnkCap: Port #0, Speed 8GT/s, Width x4, ASPM L1, Exit Latency L1 <8us ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp+ LnkCtl: ASPM Disabled; RCB 64 bytes, Disabled- CommClk+ ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt- LnkSta: Speed 8GT/s (ok), Width x4 (ok)
Edit:
$ sudo dmidecode --type 9 | grep -E 'Usage|Type|Designation'
Designation: PCIE1
Type: x1 PCI Express
Current Usage: In Use
Designation: PCIE2
Type: x16 PCI Express
Current Usage: In Use
Designation: PCIE3
Type: x1 PCI Express
Current Usage: In Use
Designation: PCIE4_M2_1
Type: x4 PCI Express
Current Usage: In Use
Huh that’s interesting, I believe that GPU should’ve been running at x8 with that CPU, but if it works then whatever I suppose.
I believe there are PCIe bandwidth benchmarks, if you really want to confirm, but I wouldn’t worry.
Also it isn’t uncommon for the device to just report the wrong speed, for example my Intel Arc reports running at x1, but benchmarks show otherwise.