Does adding more RAM increase FPS in flight simulators? Learn when it reduces stutters, how to check MSFS 2024 RAM usage, and when it will not help.
Adding more RAM improves flight simulator performance only when the PC is running short of physical memory. It can reduce paging, stutters, texture-loading delays and out-of-memory crashes, but usually does not raise average FPS when capacity is already sufficient. CPU, GPU or VRAM limits then remain unchanged.
This applies to general PC flight simulation, including Microsoft Flight Simulator, X-Plane, Prepar3D and FSX. On Xbox Series X|S, PS5 and PS5 Pro, system memory is fixed and cannot be upgraded by the user.
Does adding more RAM increase FPS?
More RAM can increase FPS only if memory pressure and paging were already suppressing performance.
RAM provides working capacity; it does not calculate the flight model or render the scene. When enough capacity is available, adding another 16 or 32 GB normally produces no meaningful frame-rate gain. When capacity is exhausted, however, Windows must compress memory or move less-active data to the page file, which can cause long frame times and visible pauses.
The most noticeable improvement is often in frame-time consistency rather than average FPS. Severe hitches may disappear and low-percentile FPS may improve, even though the frame counter remains similar during smooth sections of the flight.
| What happens during the slowdown | Is more RAM likely to help? | Why |
|---|---|---|
| Physical memory is nearly exhausted and page-file activity coincides with pauses | Yes | More active data can remain in fast physical memory |
| The simulator stutters only with complex aircraft, scenery and several external applications open | Possibly | The complete workload may exceed the available capacity |
| Plenty of memory remains available while GPU utilisation is consistently high | No | The graphics card is setting the frame rate |
| The simulator reports a main-thread or CPU limit | Usually not | Traffic, avionics, physics or object processing is the bottleneck |
| System RAM is available but graphics memory is full | No | VRAM and system RAM are separate resources |
| Memory use continually rises until the simulator crashes | Only temporarily | A memory leak may consume the extra capacity and merely delay the crash |
How can I tell if my flight simulator needs more RAM?
Your simulator needs more RAM when a repeatable problem coincides with low available memory, rising committed memory and paging, then improves when memory demand is reduced.
- Reproduce the same demanding flight. Use the airport, aircraft, weather, traffic, add-ons and camera position that normally cause the problem. Randomly comparing two different flights proves very little.
- Check total system memory. Open Windows Task Manager and inspect the Memory section while the simulator is running. Do not judge the simulator process alone because Windows, drivers, browsers, chart tools, recording software and external avionics also consume RAM.
- Watch Available and Committed memory. A large cached figure is normal: Windows uses spare RAM as a file cache and can reclaim it. The warning signs are very little available memory and committed memory approaching its displayed limit.
- Correlate paging with the stutter. Bursts of disk activity or sustained hard faults during each pause support a memory-pressure diagnosis. An occasional hard fault is normal and is not proof by itself.
- Run an A/B test. Close browsers and recording tools, disable optional scenery or traffic, restart the simulator and repeat the flight. A clear reduction in stuttering or crashing strengthens the case for more capacity.
- Rule out other limits. If several gigabytes remain available during the problem, inspect CPU, GPU, VRAM, storage and scenery-streaming behaviour instead.
A mistake we see constantly is buying RAM because Task Manager displays a high percentage, without checking what happened at the exact moment of the stutter. Our bottleneck-led simulator performance checklist covers the CPU, GPU, VRAM and storage checks that should follow.
Microsoft Flight Simulator RAM usage: what is normal?
Microsoft Flight Simulator 2020 and MSFS 2024 RAM usage varies substantially with the aircraft, airport, traffic, add-ons, background software and length of the session.
There is no single normal usage figure that applies to every flight. A quiet flight in a default aircraft is not a useful guide to the memory required by a detailed airliner at a large third-party airport. Windows caching also means two otherwise similar PCs may display different totals without either being faulty.
Judge total system pressure, not only the memory attributed to the simulator process. High system RAM use does not prove that RAM is causing low FPS, and pauses while scenery is loading can instead come from storage, online scenery streaming, cache behaviour, CPU work or VRAM pressure.
How much RAM should a flight simulator PC have?
For a modern flight simulator PC, 32 GB is a sensible practical target, while 64 GB is justified by measured memory pressure or a particularly heavy collection of add-ons and supporting applications.
| Installed RAM | Where it fits | Main limitation |
|---|---|---|
| 16 GB | Can be workable for lighter simulator workloads with few background applications | Limited headroom for detailed scenery, complex aircraft, traffic and multitasking |
| 32 GB | A balanced target for modern general-purpose flight simulation PCs | Exceptionally heavy add-on combinations can still exceed it |
| 64 GB | Useful for measured workloads that approach 32 GB, extensive add-ons, VR support or concurrent creative and recording tools | No FPS benefit if the workload already fits comfortably within 32 GB |
These are practical capacity bands, not guarantees or substitutes for checking the requirements of a particular simulator. Resolution usually affects GPU load and VRAM more directly than system RAM. Our guidance on choosing complete flight simulator PC specifications explains how RAM targets fit alongside the processor, graphics card and storage.
Does virtual RAM increase FPS?
Increasing virtual RAM or the Windows page file does not normally increase FPS because storage is far slower than physical memory.
People often use “virtual RAM” to mean the page file, although Windows virtual memory is a broader memory-management system. The page file gives Windows additional commit headroom and can prevent an application from crashing when the commit limit would otherwise be reached. It does not convert an SSD into RAM or make active paging fast.
Leave the page file enabled and, in most cases, allow Windows to manage its size. Disabling it to gain performance can instead cause out-of-memory errors, add-on failures or crashes. Increasing an undersized page file may cure a commit-limit error, but if the simulator is actively paging during flight, adding physical RAM is the proper capacity fix.
Do not confuse the page file with VRAM. Graphics memory resides on the GPU; adding system RAM does not increase a dedicated graphics card's VRAM.
Does faster or higher-capacity RAM increase FPS?
Faster RAM can produce a modest gain in CPU-limited situations, but sufficient capacity, correct channel configuration and stability matter more than the advertised memory speed.
Adding a second matched module to a PC that has only one can improve memory bandwidth by enabling the processor's intended multi-channel configuration. In that case, any gain may come from both the extra capacity and the wider memory channel, so it should not be credited to capacity alone.
Use compatible modules in the paired slots identified by the motherboard manual. Mixing separate kits can force a lower speed or cause instability even when their labels show similar specifications. Filling every memory slot may also reduce the speed that the processor and motherboard can run reliably.
Memory speed matters more when an integrated GPU shares system RAM. With a dedicated graphics card, the GPU itself and its VRAM normally have much greater influence on graphics-limited FPS. An unstable high-speed memory profile is never a performance upgrade; simulator crashes caused by RAM instability are easily mistaken for bad aircraft or scenery.
Why can FSX still run out of memory after a RAM upgrade?
FSX can still report an out-of-memory condition because it is a 32-bit application with a restricted per-process virtual address space.
Large-address-aware FSX editions can use roughly 4 GB of virtual address space on 64-bit Windows, while older or unpatched configurations may have a lower effective ceiling. Installing 32 or 64 GB of physical memory does not expand the address space available to FSX.exe, although it gives Windows and external utilities more room.
Early 32-bit Prepar3D releases have a similar restriction; later 64-bit simulators can address much more memory. An out-of-memory message can also involve system RAM, the page-file commit limit, VRAM or a faulty add-on, so our breakdown of simulator memory and address-space failures is the better diagnostic route before buying hardware.
What should I upgrade if RAM is not the bottleneck?
If memory remains available throughout the demanding flight, upgrade the component that is actually saturated rather than adding unused RAM.
- Choose a faster CPU when the main thread, traffic, complex avionics, physics or object density determines the frame rate.
- Choose a faster GPU or more VRAM when resolution, anti-aliasing, clouds, shadows or high-resolution textures trigger the slowdown.
- Choose an SSD for slow loading and file-access delays, while recognising that it will not cure a CPU- or GPU-limited frame rate.
- Reduce or isolate add-ons when the fault appears only with one aircraft, airport, traffic package or scenery combination.
- Add system RAM when repeatable testing shows physical memory exhaustion and paging under the workload you actually use.
If the evidence is mixed, use our symptom-based comparison of CPU, GPU and RAM upgrades before spending money. More RAM is valuable headroom when it solves a measured shortage; otherwise, it is simply unused capacity.