A recent firmware update for the Surface Book 2 and Surface Pro 6 is causing significant performance issues for some users. Microsoft says it’s working on a fix.

According to multiple threads on Reddit—this may be one of the first—a recent firmware update is causing some Surface Book 2 and Surface Pro 6 PCs to throttle down to about 400 MHz, a fraction of the device’s normal performance. Users have been complaining in Microsoft’s support forums as well.

Apparently, there is a temporary workaround: If you’re experiencing this issue, you can uninstall the “Microsoft ACPI-Compliant Control Method Battery” from Device Manager (WINKEY + X > Device Manager), detect hardware changes, and then restart the PC. But the performance issues will eventually, ahem, resurface because the PC will eventually reinstall the missing driver, which is related to power management.

Some have also had success with a utility called ThrottleStop, which can prevent a PC’s CPU from being throttled. However, this could be a dangerous workaround, since CPU throttling in general, and in Surface in particular, often happens specifically so that the machine doesn’t get too hot.

Fortunately, Microsoft says it is working on a fix.

“We are aware of some customers reporting a scenario with their Surface Books where CPU speeds are slowed,” a Microsoft statement reads. “We are quickly working to address via a firmware update.”

Unfortunately, this isn’t the only issue caused by a recent Surface firmware update: Last week, reports emerged about users experiencing Wi-Fi issues on multiple Surface models after an update.

Tagged with Surface Book 2, Surface Pro 6