AMD Radeon R9 270 's Advantages
Lower TDP (150W vs 300W)
AMD Radeon RX 7900 XT 's Advantages
Released 9 years late
Boost Clock has increased by 159% (2394MHz vs 925MHz)
More VRAM (20GB vs 2GB)
Larger VRAM bandwidth (800.0GB/s vs 179.2GB/s)
4096 additional rendering cores