Smart Access Memory on Radeon’s RX 5000 Series Tested – A Free Performance Boost!

Last week, AMD released their Radeon Software 21.9.1 driver for Windows OS’, delivering users of the company’s Radeon RX 5000 series GPUs a welcome performance upgrade. With AMD’s latest drivers, RX 5000 series GPU users can now utilise AMD’s Smart Access Memory feature, AMD’s optimised implementation of Resizable BAR. 

With Smart Access Memory, compatible processors and motherboards, AMD’s RX 5000 series graphics cards can now this formerly RX 6000 series GPU feature, enabling significant performance gains in some titles. Better still, unlike Nvidia’s RTX 30 series, this Resizable BAR update doesn’t require a graphics card VBIOS update to function. All AMD needs is a new driver. It just works. 

Today, we are testing this new resizable BAR implementation to see how well it works on AMD’s RX 5000 series graphics cards. To do this we will be retesting a Radeon RX 5700 XT on our Ryzen 3950X-based games test system. We will be testing a variety of popular titles, which are listed below.

Contents

– Assassin’s Creed Valhalla

– Day’s Gone

– Forza Horizon 4

– Gears 5

– Microsoft Flight Simulator

– Resident Evil Village

– The Witcher 3: The Wild Hunt

– Watch Dogs Legion

– Conclusion – Is Reliable Bar/Smart Access Memory worth it?
 

What is Smart Access Memory? 

Before now, CPUs had access to 256MB of GPU memory, an allocation size which made a lot of sense in the early 2000s. Since then, GPU memory sizes have exploded, with AMD’s Radeon high-end RX 6000 series of graphics cards featuring a whopping 16GB of GDDR6 memory. 

With AMD’s Smart Memory Access technology, AMD is granting their CPUs access to the entirety of the RX 6000 series’ frame buffer. Thanks to this access, AMD users can benefit from increased game performance within existing titles, and developers can exploit this access for further performance gains with future game releases. 

This technology will allow CPUs and graphics cards to benefit from the bandwidth offered through PCIe 4.0, as increased GPU memory access will undoubtedly result in increased bandwidth utilisation. That said, it may take a while for PCIe bandwidth to become a limiting factor with some games.   
  

Enabling Resizable Bar on an ASUS motherboard

In this article, we will be using our standard GPU/Game test system, which uses a Ryzen 9 3950X processor with Precision Boost enabled, a Crosshair VIII Formula motherboard with BIOS 3003, 16GB of Corsair 3600MHz DDR4 memory and a Radeon RX 6800 graphics card. 

Below is a screenshot of the BIOS of our X570 Crosshair VIII Formula motherboard, where we can now enable an option called “ReSize BAR” with compatible processors. This feature allows AMD’s RX 6800 series to utilise Smart Access Memory, giving users more system performance in some scenarios. 

  

Full System Specifications

Below are the full specifications of our game testing system, which we built in mid-2020 to meet the needs of future games. Today we will be testing this system with PowerColor’s Radeon RX 5700 XT Red Devil graphics card. Our review for this graphics card is available to read here. 

To help support the website, we have included Amazon affiliate links below should you wish to purchase the same or similar PC parts.   

OC3D Game/GPU Test Rig (Affiliate Links Below)

AMD Ryzen 9 3950X Processor with Prescision Boost Overdrive
ASUS ROG Crosshair VIII Formula (X570) Motherboard 
Corsair Dominator Platinum RGB Series DDR4 3600MHz (2x8GB) Memory
Corsair RM1000i Power Supply
Corsair iCUE H150i RGB Pro XT All-in-One Liquid CPU Cooler
Corsair MP600 2TB PCIe 4.0 SSD
Corsiar Obsidian 500D RGB SE Case
Windows 10 x64