Although AMD is one of TSMC’s key clients, Apple gets the highest priority for multiple reasons. Till now, the former’s 7nm capacity had been pretty constrained not only due to a wide range of products from semi-custom SoC to CPUs and GPUs, but also due to intense competition. MediaTek, Qualcomm, NVIDIA, and even Apple all leverage the foundry’s N7 node for one or more of their primary lineups. Although the latter has migrated to the N5 process (5nm) for its M1 SoC, the older chips are still based on the N7 process, taking a fair bit of available capacity.
However, the peak iPhone shipment season is in its decaying phase. As the production of the A12 and A13 processors is slowly phased out in favor of the A14 (and A15) SoC, much of the freed-up 7nm capacity is being taken over by AMD, most notably the Ryzen and Radeon products. Much of the improved stock (for the Ryzen 5000 processors) can be attributed to this shift. Both the Ryzen 5 5600X and Ryzen 7 5800X are now available at their MSRPs (or close to) at most retailers, with the Ryzen 9 SKUs also seeing a rapid drop in their selling prices.
Apple’s upcoming iPhone 13 and the A15 Bionic processors will leverage the N4 process (4nm) a refined variant of the 5nm EUV node. As such, it shouldn’t affect the production of AMD’s products as they’re all based on either the 7nm or 6nm nodes. The company is expected to make the move to the N5 process later next year with the launch of the Ryzen 6000 (Raphael processors). Rembrandt which is the successor to Cezanne, based on the Zen 3+ core and RDNA 2 graphics will leverage the 6nm node similar to the updated PS5 SoC.