AMD’s New Radeon RX 6600 XT Puts a Premium on 1080p Performance

AMD has finally announced the next RDNA2 GPU in its 2021 product stack. The Radeon RX 6600 XT is expected to slot in below the Radeon RX 6700 XT and to compete more effectively against cards like the RTX 3060. Right now, Nvidia offers ray tracing at lower price points than AMD has matched. The Radeon RX 6600 XT is intended to change that. As RDNA2 parts go, it’s one of the more interesting cards that AMD has fielded, though we aren’t entirely sure if that’s a good thing yet.

At $379, the Radeon 6600 XT comes in $100 cheaper than the Radeon 6700 XT, but that $100 difference results in a very different card. The table below summarizes AMD’s current product stack.

The Radeon 6600 XT costs about 25 percent less than the Radeon 6700 XT and it fields 25 percent fewer GPU cores, in line with expectations. The reduction in VRAM from 12GB to 8GB is not unexpected, but the dramatic reduction in L3 cache and memory bandwidth raises our eyebrows.

The 5600 XT and 6600 XT are quite different compared with the x700 cards above them in the stack. The 5700 XT and 6700 XT fielded the same number of cores, render output units, and texture multiplier units. The 6600 XT has 88 percent of the 5600 XT’s memory bandwidth and GPU cores. It compensates for this by hitting clock speeds that are 1.65x to 1.9x higher than the 5600 XT did. That kind of clock boost counts for a lot as far as keeping the GPU core fed, and the huge clock advantage the 6600 XT wields over its predecessor is more than large enough to compensate for the slightly narrower GPU core.

The memory bandwidth and L3 cuts are a topic we’ll be looking at very closely. Narrow memory buses are a hallmark of RDNA2 designs. When it launched RDNA2, AMD promised that the 128MB “Infinity Cache” on cards like the 6800 XT would fully compensate for this reduction. So far, it has. We compared IPC and memory bandwidth scaling between the 5700 XT and 6700 XT earlier this year and found no evidence of a bandwidth problem at any playable resolution. AMD prominently advertised the 6700 XT as a 1440p gaming solution, but the card is more than capable of playing in 4K if you aren’t trying to turn every single graphics option to maximum at the same time.

AMD has never disclosed how much cache it needed to effectively store data for any given resolution, so we can’t say for certain whether 32MB is enough to allow the 6600 XT to enjoy the same comfortable scaling as its bigger brothers. AMD is explicitly positioning the RX 6600 XT as a 1080p GPU option for gamers who are opting to buy high refresh rate 1080p displays. It’s also claiming that the RX 6600 XT will deliver significant performance advantages over the RTX 3060, but does not compare against the RTX 3060 Ti.

High Refresh 1080p Gaming at $379?

AMD acknowledged they were raising the price of the RX 6600 XT relative to its RDNA predecessor, but defended the decision on partly on the grounds that increasing its own prices would supposedly reduce the impact of the GPU silicon shortage. This is unlikely to be true. The mammoth markups on GPUs are being sustained by retailers and do not reflect the cost AMD or Nvidia charge the ODM. The company also noted that prices on certain components and materials have gone up, which is correct.

Still, the difference between AMD introducing a GPU at $280 versus $379 is not going to mean much when GPUs are regularly selling for a full 1.5x above MSRP. If $800 cards are flying off the shelves for $1,200, $379 GPUs will go just as fast at $569.

As ultra-high refresh rate monitors have proliferated, it makes sense that the gamers who buy them would want to also buy GPUs fast enough to drive those displays at the high frame rates they paid for, but not every high refresh rate monitor is a 1080p display. Newegg’s product list suggests there’s a 50/50 split between 1080p panels at 100Hz or above and 1440p+4K panels (764 1080p versus 685 4K + 1440p). AMD’s decision to position the 6600 XT as a high-end 1080p gaming card is not without merit, provided the card also sustains higher resolution play without its performance falling off a cliff.

The 6600 XT needs to offer excellent 1440p performance and reasonable 4K performance at reduced detail levels to be a decent purchase at $379. This is a thoroughly reasonable request and fully in line with the performance offered by the Radeon RX 5700 XT back in 2019. Our review of that GPU found it delivered playable performance in 4K ultra detail in 7 of the 10 titles we tested. The 6600 XT needs to do at least this well to illustrate any net value improvement relative to the 5700 XT.

Normally when Nvidia or AMD announces a new GPU, people question whether their published data sets are trustworthy. In this case, we’re far more curious about the performance data AMD didn’t show.

One more thing: Anyone shopping for a GPU today who also wants to use ray tracing in the future should be aware that GPU frame buffers are clearly taxed by ray tracing in a way they aren’t by rasterization. 8GB GPUs don’t always have enough VRAM to run high-end ray tracing at 4K. At 1080p, however, the 8GB VRAM buffer on the 6600 XT should be sufficient, assuming the rest of the card can handle the workload.

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