Resizable BAR technology was presented as an important advance that promised significant performance improvements, and the truth is that while it is true that in many cases there has been improvement it’s at the end It wasn’t marked that way as expected, that is, it did not fully meet the expectations created. In any case, these were free performance tweaks, and these types of tweaks are always welcome.

To this we must add another important thing, and that is The resizable BAR only works with relatively recent configurations, that is, with computers that meet a number of minimum requirements that vary depending on the platform used. NVIDIA supports this technology on the GeForce RTX 30 and GeForce RTX 40, and AMD does so on the Radeon RX 5000 and higher.

In the case of Intel, we need a Core Gen 10 (Comet Lake-S) and a motherboard with a 400 series chipset or higher and in the case of AMD we will need a Ryzen 3000 (Zen 2) and a motherboard with a 400 series chipset or higher if we are using an NVIDIA graphics card, or a motherboard with a 500 series chipset or higher if we are using an AMD graphics card.

Looking at these requirements, it goes without saying that a large number of devices that are still quite capable are left out and do not support Resizable BAR, a limitation that was overcome thanks to an open source project called ReBarUEFI. Using this mod, it was possible to activate this technology on a fairly old device and The performance improvement achieved is 6%, approximately.

This mod works as a bootstrap module that replaces the existing functions that are responsible for checking system compatibility with Resizable BAR. total, enforces compatibility and enables activation of this technology even in computers that use processors as old as second-generation Intel Core, also known as Sandy Bridge.

Enabling Resizable BAR allows the processor to access more than 256MB of graphics memory, which has varying effects depending on the game. Using an Intel Core i5-3470, which is part of the Ivy Bridge generation, and a Radeon RX 580 The performance improvement reaches up to 12% in some games. The average improvement is, as I said, 6%.

It is a very interesting mod, but since it is a solution working at the BIOS level, I recommend it be very careful if you are considering using it as it could cause problems and leave your computer completely unusable.