Intel Clarifies If Your AMD Powered PC Will Play Nice With Arc Graphics Cards
Intel would obviously love it if your next PC paired one of its Core processors with an Arc-powered graphics card, like the Arc A750 or A770 (neither of which is actually available yet, but should be soon). That doesn't mean it's going to shun support for AMD's platforms with its GPUs, though. That would be ludicrous, and lest there was any lingering doubt, Intel has taken to Twitter and cleared the air.
Let's back up a moment, because this is a somewhat nuanced discussion. As we wrote about last month, Intel recommends pairing Arc with at least a Comet Lake (10th Gen) or newer processor architecture. It's not a hard and fast requirement, but ties in with enabling a feature called Resizable BAR to deliver "optimal performance," according to Intel's Arc quick start guide.
Resizable BAR (or Smart Access Memory, SAM for short, as AMD calls it) is a featured baked into the PCI Express specification that removes memory limits between the GPU and CPU. Without the feature enabled, a CPU can pull data from a graphics card in 256MB chunks. But with Resizable BAR enabled, a CPU can access the entire frame buffer, if need be. This is important because things like textures and shaders are loaded into a graphics card's video RAM (VRAM).
Here's where things get interesting. The folks at ComputerBase put the Arc A380 through its paces on an AMD Ryzen system and compared benchmark data with and without SAM (Resizable BAR) enabled. They tested the card in a B550 motherboard with an Ryzen 5 5600X processor based on Zen 3, and you can see above it fared in that setup.
The performance was roughly equal to that of pairing the same card with a Core i5-12500 processor based on Alder Lake. In both setups, there was a pretty big jump in performance when enabling Resizable BAR/SAM, with the Ryzen platform coming within 1 percent of the Intel platform in both scenarios.
Andreas Schilling from Hardwareluxx linked to the review on Twitter and commented that Resizable BAR "seems to work for the Arc A380 in combination with a Ryzen 5 5600X after all—although this should not actually work according to @IntelGraphics." Intel's Ryan Shrout responded to the comment to clarify where things stand, and it's good news for AMD platform owners.
"Hey Andreas! To be clear, Intel Arc graphics cards should work with AMD platforms that support Resizable BAR, we just hadn't validated in time for A380 launch. My expectation for any rBAR enabled system it will work fine, including higher end cards," Shrout wrote.
So that means the A750 and A770 should both play nice on AMD platforms with Resizable BAR/SAM turned on, as well as future generation GPUs like Battlemage and Celestial. That's especially good news because users might otherwise run into weird issues with Resizable BAR turned off. In the same review mentioned earlier, it was noted that some games would crash on the AMD system with the feature disabled.
All that said, official support is likely coming anyway. A spokesperson for Intel explained to us last month that the Arc graphics rollout "involves a staggered introduction on targeted platforms" and that the company expects to "add [Resizable BAR validation] for AMD platforms with Smart Access Memory as Intel Arc graphics cards become available for sale."
