AMD Reveals Radeon RX 6500 XT: Navi 24 Lands for Low-End Desktops on January 19th

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Alongside AMD’s smorgasbord of mobile graphics offerings that were announced during today’s CES 2022 keynote, the company also has some new desktop video cards to speak about for the low-end segment of the market. On January 19[sup]th[/sup] the company will be launching their Radeon RX 6500 XT video card, the long-awaited low-end member of the Radeon RX 6000 series desktop lineup. Based on the new Navi 24 GPU, it will be hitting retail shelves for $199.

Meanwhile, joining it a bit later in the year will be the Radeon RX 6400, a second Navi 24 and OEM-only part.

Diving right in, the big hardware development driving the new desktop cards is the introduction of AMD’s new Navi 24 GPU. The fourth and seemingly final member of AMD’s Navi 2x GPU stack, Navi 24 is aimed at the low-end/entry-level segment of the market. The smallest of the Navi GPUs has seen AMD once again take a scalpel to the Navi 2x architecture, essentially cutting Navi 23 in half to deliver a part with half of the CUs, half the Infinity Cache, and roughly half of the power consumption.

But as an added kicker, AMD isn’t reusing TSMC’s 7nm process for Navi 24. Instead, the smallest of the Navi chips is being made on a 6nm manufacturing node, which we presume to be TSMC’s N6 line. This marks the second AMD GPU/accelerator we’ve seen made on 6nm – after the gigantic CDNA2 chip in the Radeon Instinct MI250X – so AMD is taking full advantage of their close working relationship with TSMC, and in turn taking advantage of the benefits offered by what’s essentially a further refined version of TSMC’s 7nm process. The switch to N6 likely isn’t adding much in the way of performance for AMD, but the roughly 15% improvement in transistor density will enable AMD to get that many more dies out of every wafer at a time when fab capacity is at a premium.

To that end, while AMD hasn’t released the official transistor counts or a die size for Navi 24, expect it to be very small, especially compared to the sizable Navi chips AMD has put out thus far.

Along with cutting down the number of CUs, another big area of transistor/die space savings for AMD on Navi 24 will come from a further reduction of the size of the Infinity Cache. That on-die SRAM cache is just 16MB for Navi 24, half the size of the cache on Navi 23 (6600). Given that Navi 23 was already the sweet spot for 1080p gaming, I’m very curious to see how Navi 24 fares in this fashion; is 16MB going to be a large enough cache for entry-level gaming? For reference, a 32-bit 1080p frame buffer is just under 8MB in size, so it’s not going to take too much to fill a 16MB cache.

In any case, with Navi 24 finally available, AMD is ready to begin shipping it in mobile (6500M/6300M) and desktop (6500 XT/6400) form factors.

Like the rest of AMD’s GPU-related announcements this morning, we’re still waiting on AMD to disclose the full specifications of the card. But at a high level, what we’re looking at is close to being half of a Radeon RX 6600 XT. The biggest shift, of course, is halving the number of CUs to 16, which brings for a total of 1024 SPs. Navi 24 is designed to be a small part and that much is reflected in the amount of hardware at hand. Offsetting part of that, however, is that the advertised game clock is a very peppy 2.6GHz, which is a couple of hundred MHz higher than even the 6600 XT. As a result, the 6500 XT should punch a bit harder than we’d otherwise expect for a 16 CU part.

As for memory configurations, pending AMD’s confirmation, I’m expecting this card to have a 64-bit memory bus. This would be in line with halving the other resources on the card, as well as consistent with AMD’s design goals to use smaller memory busses on Navi 2x parts than their Navi 1x predecessors. In that case we’re looking at just 128GB/second or so of external memory bandwidth, assuming AMD is using standard 16Gbps GDDR6 here. And as previously mentioned, the Infinity Cache has been cut down to 16MB as well. So the RX 6500 XT is going to be in the interesting position of trying to make the most of its small-but-fast Infinity Cache before bandwidth drops off significantly when going off-die. Even with so many compute resources halved, it will be interesting to see if 6500 XT can be properly fed with such a small memory bus.

But as a side benefit of stripping down Navi 2x and jumping to N6 is that power consumption has also gone down. On the mobile side this makes for 35W parts, and even on the desktop side we’re looking at power figures that AMD hasn’t been able to match since the Polaris days. Most significantly, 6500 XT’s power requirements are low enough that the card can be powered entirely via the PCIe bus – which is to say, it can be kept below 75 watts. That’s some 55W lower than the previous-generation 5500 XT, and makes the 6500 XT the first bus-powered video card we’ve seen from any vendor since the launch of the GeForce GTX 1650 all the way back in 2019.

With that said, it should be noted that staying below 75W is not a requirement for the SKU, and consequently not all board partner designs can run entirely on bus power. So expect to see a mix of both types of cards on the market, with a factory overclock being a dead giveaway that a card will require external PCIe power to meet its full power needs.

Meanwhile, AMD isn’t disclosing anything else about the Radeon RX 6400 at this time. It’s reasonable to expect the OEM-only part to be a lower configuration with lower power requirements, but past that we’ll have to see just what AMD has in store for OEMs a bit later on this year.

Product Positioning, Partner Cards, & Availability

It goes without saying that as far as product positioning goes, where the Radeon RX 6500 XT fits in to the bigger picture is a constantly shifting situation. The ongoing GPU shortage means that all logic has long since flown the coop – and isn’t coming back any time soon. So at best, we can talk about where AMD intends for it to compete, and then we’ll see where the market takes it.

As NVIDIA doesn’t have current-generation low-end video card for desktops (3050 has yet to make it out of laptops), on paper AMD has the run of the place. The only cards on the market anywhere close to it are the GeForce GTX 1650 (when it can be found) and the generations-old Radeon RX 570 4GB, which has fallen out of favor with cryptocurrency miners due to its small memory capacity. In both those cases the RX 6500 XT should be a faster card, according to AMD.
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