At KitGuru we have been running our benchmarks with Resizable BAR on since the beginning of the year. Intel has again been quite upfront about the fact that Resizable BAR, or Rebar, is essentially a requirement for its Arc GPUs; in a press briefing, Tom Peterson was as blunt as saying users who can't enable Rebar should just get a 3060 without even considering Arc!
We tested four games, with Rebar on and then with Rebar off, to take a closer look.
The results quickly show why Intel is more-or-less positioning Rebar as a requirement for Arc GPUs – the 1% lows are near enough cut in half in Assassin's Creed Valhalla and face significant reductions in both Dying Light 2 and Far Cry 6. Forza Horizon 5 is the worst offender however and becomes simply unplayable without Rebar.
While clearly a huge issue for those with systems that don't support Rebar, for me this isn’t as big of an issue as the DX11 performance is. My reasoning is that at least the last two motherboard generations from Intel and AMD do support Rebar, and in some cases even further back then that, so a fair number of PC enthusiasts should have a compatible system. And as we will get to, right now I don’t think many people who aren’t enthusiasts will be buying Arc as it’s not ready for the mainstream yet, though the Rebar situation is certainly something to keep in mind.