Microsoft is preparing to automatically enable a Windows 11 security feature on more PCs from October that may have an unwelcome side effect on gaming performance. 

The change involves Memory Integrity, also known as Hypervisor-Protected Code Integrity (HVCI). The security feature is part of Microsoft’s Virtualization-based Security (VBS) technology and is designed to protect from malicious or untrusted code.

Microsoft already enables Memory Integrity by default on many compatible Windows 11 installations. From October, however, the company plans to expand automatic activation to additional eligible machines through regular Windows quality updates. 

For most users, the change will happen without intervention. According to Microsoft, systems will be assessed for compatibility, hardware performance and driver support before the feature is enabled. Those PCs users who have previously disabled Memory Integrity will not have the feature automatically switched back on. 

The concern for gamers is the additional processing overhead created by the security technology.

Memory Integrity uses the Windows hypervisor to create an isolated environment where kernel-level code can be checked before it is allowed to run. Microsoft says the feature works more efficiently on newer processors, while older ones can experience more of an impact on performance because some security functions have to be emulated. 

The impact is set to vary between systems and games. Previous testing has shown that VBS-related security features can reduce gaming performance in some configurations, although newer hardware is less impacted. There have been some eports of frame-rate reductions of around 10%, particularly on older gaming PCs. 

It does not mean, however, that Windows 11 gaming PCs will suddenly become slower across the board. For many users, the difference may be difficult to notice.

Microsoft’s position is that the additional protection is worthwhile. Memory Integrity is designed to make it significantly harder for malware to exploit vulnerabilities in the Windows kernel, strengthening protection against attacks involving malicious drivers and low-level code. 

Gamers can check whether Memory Integrity is enabled by opening Windows Security, selecting Device security, then Core isolation details. The Memory Integrity setting can be switched off if necessary, although doing so reduces the PC’s security protection.

The wider wider rollout will begin in October and Windows 11 users with older gaming PCs may want to keep an eye on performance following their next major update.