Enable Resizable Bar with this UEFI mod on your old Gaming PC.

Resizable Bar or AMD equivalent Smart Access Memory is available on newer systems based on Intel 10th gen or AMD’s Zen3 architecture. All modern GPUs from Nvidia, AMD, and Intel now utilize resizeable bars to boost gaming performance. However, Rebar is not an entirely new technology, introduced with PCI Express 2.0 standards, but GPU manufacturers started using this feature in late 2020.

Native Resizeable bar support is available from 10th Gen Intel processor-supported motherboard. Technically, it should work on all PCI Express 2.0 systems. But the reality is different rebar support is only available on new Gen motherboards. Motherboard manufacturers could enable this feature with a UEFI update.  

Without native Rebar support, we have seen a massive performance hit with newer GPUs that utilize this feature, especially Intel ARC graphics cards. Intel officially recommends a native resizeable bar-supported motherboard for their ARC GPUs for optimal performance. Arc graphics cards lose around 25% of performance without Resizeable bar support. Nvidia and AMD cards also suffer performance loss without Rebar, but not as crazy as Arcs. 

Thanks to the open-source tool ReBarUEFI, you can enable Resizeable Bar support with this modding tool on older motherboards that officially didn’t support rebar. It injects the Resizebar module option in UEFI that executes on every boot.



ReBarUEFI’s developer confirms that they have successfully tested Resizable BAR on a Core i5-3470 system with Sapphire Nitro+ RX 580 8GB GPU and see a 12% increased performance. Tomshardware confirms that this mod works even on the Sandy Bridge platform – a decade-old platform launched in 2011. 


4G Decoding is a requirement for this mod. The Bar size will be limited to 1GG to 512MB without 4G decoding. If the 4G Decoding isn’t available on your UEFI, you can use the UEFITool utility to unlock these settings. Moreover, CMS must be disabled for 4G decoding to work smoothly. Of course, this process needs technical knowledge as some motherboards need DSDT patching, which is difficult for regular users. The developer lists a page of working motherboards and the required patch on the tested system. 

Native Resizeable bar support is only available on Intel 10th gen and later systems, as we mentioned earlier. Rebar debuted in the Ryzen 5000 series for AMD systems. GPU upgrade path became worthless for the systems that came before 2020. Many gamers remain with Intel 6th – 9th Gengaming systems, and they provide decent gaming performance even on the latest games. The same goes for 2nd and 3rd Gen Ryzen processors. However, the absence of Resizeable bar support forces these users to buy new motherboards and processors. This mod helps those who want to upgrade their GPU without replacing the entire system. 

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