AMD’s Radeon RX 7900 series GPUs suffer from multiple architectural flaws. The poor clock-power curve is the most pressing issue on the table, one that ruined the chipmaker’s plans to break the 3GHz barrier. The 50% performance-per-watt uplift target is also squarely out of the window. Kepler has discovered another hardware flaw plaguing the Navi 31 die.
The RX 7900 GPUs available at retail are based on premature A0 silicon featuring dysfunctional shader prefetch units. Although not as damaging as the efficiency or clock scaling failure, it may lead to stutters and poor frame times. Software-level prefetchers can take over, but they aren’t quite as efficient as their hardware counterparts. AMD may fix this with future revisions, but we have no guarantee. The Radeon RX 7700 XT, leveraging the Navi 33 die should fix it.