Your Windows 11 PC is about to get a security upgrade it never asked for, and on an older gaming rig that extra layer of protection may quietly cost you frame rates. Microsoft confirmed it will start switching on Memory Integrity for far more eligible devices through routine monthly updates beginning in October, a change that security experts welcome but PC gamers are watching warily.
What Microsoft is actually switching on
Memory Integrity, also called Hypervisor-protected Code Integrity (HVCI), is a Windows security layer that checks kernel-mode code and drivers against a trusted list before letting them run, and the hypervisor keeps that check isolated from the rest of the OS. Malicious code simply cannot load into the kernel unless it passes the scan. Microsoft says the feature already runs by default on clean installs and on Secured-core PCs, and the October rollout extends it to systems that were upgraded from older Windows versions or that shipped with the feature turned off.
Where Virtualization-based Security (VBS), which Memory Integrity depends on, is not yet active, the same quality updates will turn it on as well. Microsoft frames the move as part of its push to be secure by default, but it is also clear about the trade-off on some hardware.
Why your FPS could take a hit
The performance cost depends heavily on the processor. Current-generation CPUs with hardware support for virtualization handle the extra verification with little change to frame rates. Older chips that rely on software emulation for the same checks can show lower and less steady FPS in select games, which is exactly what caught the attention of the PC gaming crowd.
- Modern CPUs: minimal impact, mostly within normal frame-rate variance.
- Older CPUs: possible lower and less steady FPS in certain titles.
- Incompatible drivers: the most common reason the feature stays off today, often showing a “driver can’t load on this device” error.
Driver compatibility has historically been the bigger blocker than raw speed. If you have pushed for maximum frame rates on a gaming desktop or an RTX-powered SFF build, the added screening can introduce a new variable you did not plan for.
What stays on, what you can turn off
Microsoft promises it will respect existing choices. Devices where Memory Integrity was already disabled manually, through the registry, Group Policy, or Intune, will keep that configuration and will not be flipped on by this rollout. Only machines where the setting has never been touched are in line to be switched on automatically.
The company’s guidance for gamers who want frame rates above everything else is simple: turn Memory Integrity off before a session and back on after. Checking the current state takes seconds. Type “Core Isolation” into the Windows search bar to open the relevant page in Windows Security, where the Memory Integrity toggle sits under Device security.
Should you turn it off?
For most people the answer is no. Keeping Memory Integrity on materially raises the bar against kernel-level attacks, and on modern hardware the frame-rate cost is usually invisible. The decision is really aimed at owners of older CPUs who notice a real, steady drop and are willing to accept a weaker security baseline in exchange. If you spend more time tuning performance than worrying about exploits, it is worth checking the setting before the October updates land and deciding in advance, rather than being surprised mid-game when the frame counter dips.
| Scenario | What to expect |
|---|---|
| Modern CPU, clean install | Feature already on, negligible FPS impact |
| Older CPU, upgraded from Win 10 | Possible lower, less steady FPS in select titles |
| Manually disabled today | Stays off, rollout will not re-enable it |
| Untouched setting | Switched on automatically starting October |
