[Hardware] Arc A770 Loses Up to 24 Percent Performance Without Resizable Bar

[-Sn!PeR-]

 

Intel has revitalized the midrange graphics card market with the company's latest Arc A770, which will make its way into the list of best graphics cards. Starting at $329, the Arc Alchemist graphics card brings GeForce RTX 3060-like performance to the table with Resizable BAR (ReBAR) enabled, of course. But, without ReBAR or similar technology like Smart Access Memory (SAM), it's another story.

 

With Arc, Intel recommends potential consumers make sure their systems support ReBAR or SAM. The chipmaker has been very open about it and publishes it on its website(opens in new tab). ReBAR isn't mandatory but recommended since the chipmaker built its graphics cards and drivers around ReBAR. Intel fellow Thomas A. Peterson (TAP) said, "If you have an older PC without ReBAR support, just buy an RTX 3060, don't bother with Arc." Therefore, it's safe to assume that Arc graphics cards suffer a performance penalty on systems that lack support for ReBAR. Media news outlet TechPowerUp(opens in new tab) has tested the Arc A770 with ReBAR disabled, and the results speak for themselves.

 

Without ReBAR, the Arc A770's performance, on average, plummeted to 77% at 1080p (1920x1080), 76% at 1440p (2560x1440), and 80% at 4K (3840x2160). Arc owners who don't have a system with ReBAR are essentially losing almost a quarter of the performance from their graphics cards. Intel's other Arc offerings, such as the A750 and A380, will also undergo performance losses. However, we don't know to what degree.

 

Nonetheless, TechPowerUp's results don't paint the entire picture. The publication noted that the games suffered from stutters and were simply unplayable without ReBAR. Moreover, the lack of ReBAR significantly impacted the Arc A770 across 25 titles, so it's not just AMD- or Nvidia-specific titles.

 

In addition to testing ReBAR, TechPowerUp also evaluated whether the speed of the expansion slot impacts the Arc A770's performance. As a reminder, the Arc A770 comes with a conventional PCIe 4.0 x16 interface. However, the tests revealed that PCIe 3.0 is still plenty for the Arc A770 as long as ReBAR is enabled. Furthermore, TechPowerUp only recorded a performance difference of up to 2% between PCIe 3.0 and PCIe 4.0, so ReBAR support is more important than the expansion slot.

 

Regarding ReBAR, only Intel 10th Generation Comet Lake, 11th Generation Rocket Lake, and 12th Generation Alder Lake processors support that feature. As for AMD, SAM support is only present on Ryzen 3000 Zen 2 chips and newer. So while Arc's performance looks attractive and priced fairly, its requirements effectively lock out users with older systems. Arc also demands Windows 10 20H2 or Windows 11 as the operating system, so Windows 7 users, who are reluctant to upgrade, are also out of the picture.

 

The Arc A770 will hit the retail market on October 12, starting at $329. If you plan to upgrade to Arc for gaming, ensure your system supports ReBAR or SAM. If not, you're better off picking up a Radeon RX 6650 XT for $285 or even the GeForce RTX 3060 at $369.

 

Source.