Fix SM Bus Controller driver
SM Bus Controller is a small chipset part Windows cannot name. On an Intel PC, run Intel's Chipset INF Utility; on a Ryzen PC, install AMD's chipset driver. Your PC or motherboard maker's chipset package also works and is the first place to look.
Checked October 30, 2026 against the manufacturer's own pages.
Driver downloads
| Driver | Version | Released | Size | Windows | Download |
|---|---|---|---|---|---|
| Intel Chipset INF Utility | 10.1.20658.8883 | January 8, 2026 | 98.1 MB | Windows 10 and 11, 64-bit | Download from intel.com |
Values copied from the manufacturer's page on October 30, 2026. The file always downloads from the manufacturer, never from this site.
Hardware IDs on this page
| Hardware ID | Device name |
|---|---|
PCI\VEN_8086&DEV_51A3 | Alder Lake PCH-P SMBus Host Controller |
PCI\VEN_8086&DEV_43A3 | 500 Series Chipset Family SMBus |
PCI\VEN_8086&DEV_06A3 | 400 Series Chipset Family SMBus |
PCI\VEN_8086&DEV_A323 | 300/C240 Series Chipset Family SMBus Controller |
PCI\VEN_8086&DEV_7AA3 | 600 Series Chipset Family SMBus |
PCI\VEN_1022&DEV_790B | FCH SMBus Controller |
Match the first line of Hardware Ids in Device Manager (Properties, Details) against this list. Names come from the public PCI ID Repository.
The short version
What to install and where it comes from. Every link goes to the manufacturer or Microsoft, never to a copy.
Official files only, nothing bundled
Step by step
Read the hardware ID
In Device Manager, open SM Bus Controller under Other devices. On the Details tab choose Hardware Ids. VEN_8086 is Intel, VEN_1022 is AMD.
Run Windows Update first
Open Settings, Windows Update, Check for updates, then Advanced options and Optional updates. Install any chipset or system driver listed there.
Try your PC or board maker
Search your model on the maker's support page and install the chipset package it lists. Makers test that package against your exact machine.
Intel PCs: run the INF Utility
If the ID starts with VEN_8086, download Intel's Chipset INF Utility, run SetupChipset.exe and restart. It adds the names Windows was missing.
AMD PCs: install the chipset driver
If the ID starts with VEN_1022, pick your socket and chipset on AMD's drivers page and install the chipset driver. Restart afterwards.
Scan for changes
Back in Device Manager use Action, Scan for hardware changes. The entry should now read as a named SMBus controller under System devices.
What the entry really is
SMBus stands for System Management Bus. It is a slow two-wire link inside the chipset. Board firmware and Windows use it to read small chips, for example the data chip on a memory stick, and some temperature or fan sensors. Windows lists the device as SM Bus Controller when it finds the hardware but has no INF file saying what it is. That is why it sits under Other devices with a yellow mark rather than under System devices.
IDs behind the name
On Intel machines the controller is part of the chipset, so the ID changes with the chipset generation. The table shows common examples copied from the public PCI ID list. On AMD machines the same job is done by the FCH SMBus Controller. You do not need a different driver for each ID. One chipset package from Intel or AMD covers every ID in its family.
Which package clears it
For Intel, the Chipset INF Utility is the matching download. Intel describes it as installing INF files so Windows can show the correct name for a part in Device Manager. It does not add USB or graphics drivers. Intel also has a support article for this exact symptom, where an SMBus entry and a firmware hub entry show a yellow question mark. For AMD, the chipset driver on the AMD drivers page includes the files for the FCH SMBus part.
On a laptop, start with the maker’s page. Laptop makers often bundle chipset files with other platform software, and mixing a generic package over theirs can leave version mismatches.
Questions
What does the SM Bus Controller do?
It is a low-speed bus the chipset uses to talk to small parts such as memory module data chips and some sensors. Nothing you see on screen depends on it, but monitoring tools and power features can.
Is the yellow mark harmful?
It does not damage anything. The entry only means Windows has no name or driver for the part. Clearing it removes the warning and lets sensor tools read the bus.
The Intel utility finished but the mark stayed.
Restart, then use Scan for hardware changes. If it still shows, right-click the entry, choose Update driver, Browse my computer, and point to the folder the maker's chipset package unpacked.
Does the Intel utility install a new driver?
Intel says it installs INF files that tell Windows the product name of chipset parts. It is mostly a naming fix, so expect the entry to be renamed rather than a large change in behaviour.