Tuesday, November 15th 2022
AMD Confirms Radeon RX 7900 Series Clocks, Direct Competition with RTX 4080
AMD in its technical presentation confirmed the reference clock speeds of the Radeon RX 7900 XTX and RX 7900 XT RDNA3 graphics cards. The company also made its first reference to a GeForce RTX 40-series "Ada" product, the RTX 4080 (16 GB), which is going to launch later today. The RX 7900 XTX maxes out the "Navi 31" silicon, featuring all 96 RDNA3 compute units or 6,144 stream processors; while the RX 7900 XT is configured with 84 compute units, or 5,376 stream processors. The two cards also differ with memory configuration. While the RX 7900 XTX gets 24 GB of 20 Gbps GDDR6 across a 384-bit memory interface (960 GB/s); the RX 7900 XT gets 20 GB of 20 Gbps GDDR6 across 320-bit (800 GB/s).
The RX 7900 XTX comes with a Game Clocks frequency of 2300 MHz, and 2500 MHz boost clocks, whereas the RX 7900 XT comes with 2000 MHz Game Clocks, and 2400 MHz boost clocks. The Game Clocks frequency is more relevant between the two. AMD achieves 20 GB memory on the RX 7900 XT by using ten 16 Gbit GDDR6 memory chips across a 320-bit wide memory bus created by disabling one of the six 64-bit MCDs, which also subtracts 16 MB from the GPU's 96 MB Infinity Cache memory, leaving the RX 7900 XT with 80 MB of it. The slide describing the specs of the two cards compares them to the GeForce RTX 4080, which is what the two could compete more against, especially given their pricing. The RX 7900 XTX is 16% cheaper than the RTX 4080, and the RX 7900 XT is 25% cheaper.
The RX 7900 XTX comes with a Game Clocks frequency of 2300 MHz, and 2500 MHz boost clocks, whereas the RX 7900 XT comes with 2000 MHz Game Clocks, and 2400 MHz boost clocks. The Game Clocks frequency is more relevant between the two. AMD achieves 20 GB memory on the RX 7900 XT by using ten 16 Gbit GDDR6 memory chips across a 320-bit wide memory bus created by disabling one of the six 64-bit MCDs, which also subtracts 16 MB from the GPU's 96 MB Infinity Cache memory, leaving the RX 7900 XT with 80 MB of it. The slide describing the specs of the two cards compares them to the GeForce RTX 4080, which is what the two could compete more against, especially given their pricing. The RX 7900 XTX is 16% cheaper than the RTX 4080, and the RX 7900 XT is 25% cheaper.
166 Comments on AMD Confirms Radeon RX 7900 Series Clocks, Direct Competition with RTX 4080
Either way, very much looking forward to benchmarks of these! None, since it doesn't launch till December 3rd?
Everything will look good if the price is right. I'm curious how those cards will stack against NVidia. If the 7900XTX can reach 4090 and can beat 4080 comfortable that is a huge win for consumers with the price which could have been lower though but it is not bad. For NV pricing? Well, I'm kinda losing words how to call this since it's insanely crazy?
I also expect the 7800XT to be a reasonable amount faster than the 6950XT (+15% to 20%) but in a much lower BOM so I would not be surprised if AMD have done what you said by making it so the XT can be made by anything that is either partially defective, does not meet the performance bin for the XTX or has a failed MCD bond.
If true though I suspect it will mean a lot of variance in how the XT overclocks because you could have a die that was defective (missing shaders) but clocks great, a die that failed the bin so clocks poorly or a die that is actually an XTX die but one of the MCD bonds didn't work properly so it needs to be sold as an XT. This leads me to think the driver power limits will be pretty restricted for the XT version because otherwise I can imagine people saving the $100, buying the XT and then overclocking the snot out of it (a bit like the 7950 vs 7970).
Of course they're not in the same supply-constrained market today, so they're going to need to be a bit more flexible and more willing to "unnecessarily" sell parts as a lower bin than they actually qualify for - this has been the norm in chipmaking forever, after all. But I still expect their first push to be plenty of XTXes, and notably fewer XTs. This also (assuming the XT PCB is also used for the 7800 XT) makes the XTX having its own PCB more understandable - it's likely supposed to have enough volume to recoup its own costs, while the XT is designed to be an in-between SKU with more cost optimization. Which is kind of crazy for a $900 GPU, but it's not like those cost optimizations are bad, it just looks slightly less over-the-top.
It will definitely be interesting to see what the power limits for the XT will be like - AMD has had some pretty strict power limits for lower end SKUs lately, like the RX 6600, but nothing like that for a high end, high power SKU. It also raises the question of what premium AIB models of the XT will be like, as AMD is making it pretty clear that there'll be heavily OC'd partner XTXes. That might also be part of the pricing strategy here - with a mere 10% difference, ultra-premium 3GHz XTs don't make as much sense, as they'd cost more than a base XTX - so the upsell to an equally ultra-premium XTX would be relatively easy. And AMD makes money on selling chips after all, not whole GPUs, so they'd always want to sell the more premium SKU.
Also definitely looking forward to seeing what the 7800 XT will be - a further cut down Navi 31? If Navi 32 has the rumored CU count, they'd need another in-between SKU (the poor competitive performance of the 6700 XT demonstrated how they can't leave gaps that big in their lineup), but with die sizes being this moderate and GPUs being relatively affordable and easy to tape out compared to most chips (being massive arrays of identical hardware helps!) I could see AMD launching more Navi 3X dice than 2X from that fact alone.
Selling dies with lower componentry due to yield issues is another matter, albeit a legitimate one.
Nothing worse than selling highest end SKU, only to artificially limiting it in order to sell higher SKU later down the line
Couldn't careless about my 3090 or 4090 if they were being 50% working die
I don't care about having the best, but I do care about having the best in the price and performance range I consider sensible for my needs. Then why do you care about a locked voltage/frequency curve?
IMHO the real cutting edge is chased by AMD right now, doing chiplet GPUs that are the only possible way of continuously moving GPU performance forward without creating massive monolithic dies that need upwards of 400W to speed ahead.
I also don't get why people get hung up on dies being fully enabled or not. You get the product benched as-is and you know very well what it is capable of.