Windows 11 ships with a security feature called Virtualization-Based Security (VBS), and its most visible piece — Memory Integrity, also known as Core Isolation or HVCI — can quietly cost you frames. If your gaming laptop feels a little slower than the benchmarks you read, VBS is one of the first things worth checking.
What VBS and Core Isolation do
VBS uses the CPU’s virtualization extensions to wall off a secure region of memory that even the kernel cannot freely touch. Memory Integrity (HVCI) runs inside that protected space and verifies drivers before they load, which blocks a whole class of malware. It is genuinely good security — but that isolation adds overhead to memory access and driver calls, and games are sensitive to exactly that.
The real-world performance cost
| Workload | Typical FPS impact with VBS on |
|---|---|
| GPU-bound AAA at 1440p | 0-3% (often unnoticeable) |
| CPU-bound esports at high fps | 3-8% |
| Simulation/strategy (heavy CPU) | 5-10% |
| 1% lows / frame pacing | Can worsen noticeably |
When you are GPU-limited — the usual case at 1440p with demanding settings — VBS costs almost nothing. The hit shows up when the CPU is the bottleneck: competitive shooters chasing 240+ fps, and CPU-bound sims where every bit of memory latency matters.
How to check if it is on
Press Start, type msinfo32, and look for “Virtualization-based security” — it will say Running or Not enabled. You can also open Windows Security > Device security > Core isolation to see the Memory Integrity toggle. Many clean-installed Windows 11 machines have it on by default; some OEM images ship it off.
Should you turn it off?
This is a security-versus-speed tradeoff, so decide deliberately. If you are chasing maximum competitive frame rates and you are careful about what you install, disabling Memory Integrity can recover a few percent and tighten frame pacing. If the laptop is also your work or school machine, leave it on — a few frames is not worth weakening driver-level protection.
How to disable (if you choose to)
Go to Windows Security > Device security > Core isolation and toggle Memory Integrity off, then reboot. That disables HVCI while leaving lighter protections in place. Fully disabling VBS also requires turning off related features (like the virtual machine platform) and is rarely necessary just for gaming. Re-enable it in one click if you notice no benefit.
Why clean installs differ from OEM images
One source of confusion: two people with the identical laptop model can see different results because VBS defaults vary by how Windows was installed. A fresh Windows 11 clean install on hardware that supports it often enables Memory Integrity by default, while many OEM factory images ship with it off to avoid driver-compatibility complaints. So if you clean-installed Windows and suddenly felt a few frames slower, VBS turning itself on is a prime suspect.
Memory Integrity also requires compatible drivers; an incompatible one can silently prevent it from enabling, or cause it to block a driver you need. After any major Windows feature update, it is worth re-checking the toggle in Windows Security, because updates occasionally flip it back on. For gamers who have decided the security tradeoff is worth the frames, the routine is simple: verify the state in msinfo32 after big updates, and keep a mental note that “slower after an update” often traces back to a security feature quietly re-enabling rather than any hardware fault.
FAQ
Will disabling Core Isolation break anything?
No — it is designed to toggle safely. You lose the extra malware protection HVCI provides, but games, drivers, and apps continue to work normally.
Why did an update turn it back on?
Feature updates and some driver packages can re-enable Memory Integrity. After a big Windows update, re-check the toggle if you had deliberately turned it off.
Bottom line
VBS/Core Isolation is real security with a real — but usually small — performance cost. GPU-bound gamers can leave it on and never notice; competitive players chasing high frame rates on a fast laptop may reclaim 3-8% and smoother pacing by disabling Memory Integrity. Check msinfo32, weigh the tradeoff, and choose on purpose rather than by default.
