--- title: Enable Resizable BAR On Unsupported Motherboards | daily.dev description: A project called arc-rebar enables Intel GPUs to work more efficiently on motherboards that do not support resizable BAR. It requires Debian or Ubuntu and a... canonical: https://daily.dev/posts/enable-resizable-bar-on-unsupported-motherboards-srlywyxud twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Enable Resizable BAR On Unsupported Motherboards | daily.dev og:description: A project called arc-rebar enables Intel GPUs to work more efficiently on motherboards that do not support resizable BAR. It requires Debian or Ubuntu and a... og:url: https://daily.dev/posts/enable-resizable-bar-on-unsupported-motherboards-srlywyxud og:image: https://api.daily.dev/og/posts/srLYwYXud.png og:image:alt: Enable Resizable BAR On Unsupported Motherboards og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Enable Resizable BAR On Unsupported Motherboards **[Hackaday](https://daily.dev/sources/hackaday)** · 2 min read · 0 upvotes · 0 comments ## Summary A project called arc-rebar enables Intel GPUs to work more efficiently on motherboards that do not support resizable BAR. It requires Debian or Ubuntu and a supported Intel GPU. The tool uses an initramfs-based fix that runs before the GPU driver loads and performs the BAR configuration. In testing with an Intel Arc B580 on a 2015-era Xeon motherboard, bandwidth jumped from 15 GB/s to 392 GB/s. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How can I enable resizable BAR for my Intel Arc GPU on a motherboard that doesn't support it? The arc-rebar project on GitHub provides an initramfs-based fix for Debian or Ubuntu that runs before the GPU driver loads. It removes the pcieport kernel driver from the GPU's internal PCIe bridge, manually sets the GPU's BAR size, and has the kernel re-probe devices so it detects the larger BAR. It requires a supported Intel Arc GPU. _Developers tuning Intel Arc performance on older boards can track hardware hacks like this on daily.dev._ ### Why does resizable BAR matter so much for Intel Arc GPUs specifically compared to AMD or Nvidia? Intel's Arc GPU generations were designed with resizable BAR (ReBAR) as a core feature, unlike AMD and Nvidia GPUs whose designs predate widespread ReBAR support. Without ReBAR enabled, only the standard 256 MB of VRAM gets mapped into the PC's address space instead of much more, which cripples performance on motherboards that don't enable it during PCIe bus enumeration. _Anyone choosing a GPU for an older motherboard can weigh these ReBAR trade-offs via daily.dev._ ### What performance difference does fixing resizable BAR make for an Intel Arc B580 GPU? On a 2015-era Intel Xeon motherboard, enabling proper resizable BAR support for an Intel Arc B580 GPU increased bandwidth from 15 GB/s to 392 GB/s. This fix was achieved using the arc-rebar initramfs-based script rather than a BIOS-level DXE module injection. _Developers squeezing more life from older hardware can follow fixes like this on daily.dev._ ## Similar posts on daily.dev - [ReBAR Code Cleaned Up For Linux 6.19 Along With A Few New PCIe Controller Drivers](https://daily.dev/posts/rebar-code-cleaned-up-for-linux-6-19-along-with-a-few-new-pcie-controller-drivers-zi12ku6yh) · Phoronix · 0 upvotes · 0 comments - [No, Resizable BAR isn’t the universal performance booster you think it is](https://daily.dev/posts/no-resizable-bar-isn-t-the-universal-performance-booster-you-think-it-is-tjf2c5a2m) · XDA Developers · 1 upvotes · 0 comments - [PCI Resizable BAR Improvements Heading To Linux 6.19](https://daily.dev/posts/pci-resizable-bar-improvements-heading-to-linux-6-19-6eu32ydi3) · Phoronix · 1 upvotes · 0 comments - [Nvidia's secretly disabling Resizable BAR in your games, even though your BIOS says it's on](https://daily.dev/posts/nvidia-s-secretly-disabling-resizable-bar-in-your-games-even-though-your-bios-says-it-s-on-vtkuc41sd) · XDA Developers · 0 upvotes · 0 comments - [I still see Resizable BAR disabled on many PCs, and it is quietly costing people free GPU performance](https://daily.dev/posts/i-still-see-resizable-bar-disabled-on-many-pcs-and-it-is-quietly-costing-people-free-gpu-performanc-pwhjappnw) · XDA Developers · 0 upvotes · 0 comments --- Tags: [#linux](https://daily.dev/tags/linux), [#gpu](https://daily.dev/tags/gpu) [View this post on daily.dev](https://daily.dev/posts/enable-resizable-bar-on-unsupported-motherboards-srlywyxud) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Enable Resizable BAR On Unsupported Motherboards","url":"https://daily.dev/posts/enable-resizable-bar-on-unsupported-motherboards-srlywyxud","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/enable-resizable-bar-on-unsupported-motherboards-srlywyxud"},"datePublished":"2026-10-26T23:16:06.800Z","dateModified":"2026-10-26T23:52:44.965Z","description":"A project called arc-rebar enables Intel GPUs to work more efficiently on motherboards that do not support resizable BAR. 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