What Is Resizable BAR (ReBAR)? Should You Enable It for Gaming?
Lennon Byatt
If you've recently upgraded your gaming PC or installed a new graphics card, you may have come across a BIOS setting called Resizable BAR (often shortened to ReBAR).
Many gamers enable it without knowing what it actually does, while others wonder whether it's worth turning on at all.
In this guide, we'll explain what Resizable BAR is, how it works, its benefits, and whether you should enable it for your gaming PC.
Looking for the latest gaming hardware? Browse AWD-IT's range of Gaming PCs:
https://www.awd-it.co.uk/gaming-pc.html
Recommended 1440p Gaming PC Specifications
For the best balance of performance and value, we recommend:
| Component | Recommendation |
|
CPU
|
AMD Ryzen 7 7800X3D
|
|
GPU
|
NVIDIA GeForce RTX 5070 or AMD Radeon RX 9070 XT
|
|
RAM
|
32GB DDR5 6000MHz
|
|
Storage
|
2TB PCIe Gen4 NVMe SSD
|
|
Motherboard
|
B650
|
|
PSU
|
750W 80 PLUS Gold
|
This specification is capable of running modern AAA games at high frame rates while providing plenty of headroom for future releases.
Browse AWD-IT's latest AMD Ryzen Processors:
https://www.awd-it.co.uk/components/cpu-processors/amd-cpu.html
What Is Resizable BAR?
Resizable BAR is a PCI Express feature that allows your processor to access the full memory (VRAM) of your graphics card instead of reading it in smaller chunks.
Traditionally, CPUs could only access a limited portion of GPU memory at one time. Resizable BAR removes this restriction, allowing data to be transferred more efficiently between the CPU and graphics card.
The result can be improved gaming performance in supported titles.
Does Resizable BAR Increase FPS?
Yes—but not in every game.
Depending on the title and hardware configuration, enabling Resizable BAR can improve gaming performance by anywhere from 1% to 10%.
Games that benefit the most often include:
- Cyberpunk 2077
- Assassin's Creed Mirage
- Forza Horizon 5
- Horizon Forbidden West
- Starfield
Other games may show little or no difference.
Resizable BAR can improve gaming performance
Which Hardware Supports Resizable BAR?
Most modern gaming hardware supports ReBAR.
AMD
- Ryzen 5000 Series
- Ryzen 7000 Series
- Ryzen 9000 Series
- Radeon RX 6000, 7000 and newer graphics cards
NVIDIA
- GeForce RTX 30 Series
- RTX 40 Series
- RTX 50 Series
Browse AWD-IT's latest Graphics Cards:
Coil whine is an electrical characteristic rather than a fault
How to Enable Resizable BAR
Enabling ReBAR is usually straightforward.
You'll generally need to:
- Update your motherboard BIOS.
- Enable Above 4G Decoding.
- Enable Resizable BAR Support.
- Save your settings and restart your PC.
Your graphics card drivers should automatically detect that ReBAR is enabled.
Does It Work With Every Game?
No.
Resizable BAR depends on both game optimisation and GPU driver support.
Some games see noticeable improvements, while others perform almost identically with the feature enabled.
Fortunately, enabling ReBAR won't usually reduce performance.
Recommended Gaming Build
For an excellent gaming experience in 2026:
| Component | Recommendation |
|
CPU
|
AMD Ryzen 7 7800X3D
|
|
GPU
|
RTX 5070 or RX 9070 XT
|
|
RAM
|
32GB DDR5 6000MHz
|
|
Storage
|
2TB NVMe SSD
|
Browse AWD-IT's latest:
- Gaming PCs
https://www.awd-it.co.uk/gaming-pc.html
- AMD Processors
https://www.awd-it.co.uk/components/cpu-processors/amd-cpu.html
- Graphics Cards
Enable G-SYNC or FreeSync
Adaptive sync technologies can help smooth gameplay while reducing unnecessary GPU workload.
Use a High-Quality Power Supply
Power delivery can influence coil whine.
A reliable PSU with stable voltage output may help minimise electrical noise.
Browse AWD-IT's range of Power Supplies:
Power delivery can influence coil whine
Let the Card "Bed In"
Some users report that coil whine becomes less noticeable after several weeks of regular gaming.
While this isn't guaranteed, it can happen as components settle over time.
Should You Return a Graphics Card?
If coil whine is extremely loud and disruptive, it's worth contacting the retailer to discuss your options.
However, because coil whine is generally considered a normal characteristic of modern graphics cards, it may not always qualify as a manufacturing fault.
If your graphics card performs normally in every other way, keeping it is often the best option.
Best Sim Racing Setup for Beginners: Start With the Essentials
You don’t need a full cockpit immediately. A well‑chosen beginner setup helps you develop skills faster and keeps costs under control.
1. Steering Wheel and Pedals (Top Priority)
Your wheel and pedals are the most important part of any sim racing rig. Force feedback allows you to feel grip changes, kerbs, and steering resistance—crucial for learning car control.
Beginner tip: Focus on force feedback quality rather than raw power.
Your wheel and pedals are the most important part of any sim racing rig. Force feedback allows you to feel grip changes, kerbs, and steering resistance—crucial for learning car control.
Creators in attendance
Stacked lineup
Experience zones
Arcades · Sim rigs · PCs
Tech on display
Latest gen builds
Verdict
Showroom certified
Pick Your Tier
We've named each tier after a tournament stage, because let's be honest, that's exactly the kind of thing we'd do. Find your budget and dive in.
Group Stage
Round of 32
Quarter Final
World Cup Final
Upgrade in Stages
You don't have to replace everything at once.
A sensible upgrade path might look like:
- Upgrade your graphics card.
- Increase your RAM to 32GB.
- Add a larger NVMe SSD.
- Upgrade your CPU later if needed.
This spreads the cost over time while keeping your gaming PC competitive.
You don't have to replace everything at once
Expected Gaming Performance
|
Game
|
1440p High
|
1440p Ultra
|
|
GTA 6 (Predicted)
|
120 FPS
|
90 FPS
|
|
Cyberpunk 2077
|
120 FPS
|
95 FPS
|
|
Black Ops 7
|
180+ FPS
|
150+ FPS
|
|
Fortnite
|
240+ FPS
|
200+ FPS
|
Performance will vary depending on drivers, game updates and graphics settings.
12. Optimise Your Internet Connection
Although internet latency is different from input lag, a stable wired Ethernet connection provides a much better online gaming experience than unreliable Wi-Fi.
The 7800X3D pairs exceptionally well with today's most powerful graphics cards
Best Graphics Cards to Pair with the Ryzen 7 7800X3D
The 7800X3D pairs exceptionally well with today's most powerful graphics cards, including:
- AMD Radeon RX 9070 XT
- NVIDIA GeForce RTX 5070
- NVIDIA GeForce RTX 5080
If you're still deciding which GPU to buy, check out:
Best Graphics Card for 1440p Gaming
https://www.awd-it.co.uk/gaming-news/best-graphics-card-for-1440p-gaming-2026.html
You can also browse AWD-IT's latest Graphics Cards:
Frequently Asked Questions
Does ReBAR increase VRAM?
No.
It simply allows the CPU to access the GPU's existing memory more efficiently.
Can ReBAR damage my PC?
No.
It's an officially supported PCI Express feature and is completely safe to enable on compatible hardware.
Do I need a BIOS update?
Possibly.
Many older motherboards received ReBAR support through BIOS updates, so it's worth checking your motherboard manufacturer's website.
Final Verdict
Resizable BAR is one of the easiest gaming optimisations available today.
While it won't transform your gaming performance overnight, enabling it can provide small but worthwhile improvements in supported games without costing a penny.
If you're building a new gaming PC or upgrading your current system, it's well worth checking whether your hardware supports ReBAR and making sure it's enabled.
Looking for compatible hardware? Browse AWD-IT's latest Gaming PCs, Graphics Cards, Processors, and Motherboards to build a gaming system that's ready for the latest technologies.
Related Guides
- Best Graphics Card for 1440p Gaming
- RTX 5070 vs RX 9070 XT
- Best PSU for RTX 5070
- Best Gaming PC Under £1500 UK
- Best SSD for Gaming in 2026
- How Much RAM Do You Need for Gaming?
