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Maximum PC Article from 2008
(media.tech.lgbt)
Nintendo Wii: Sold like gangbusters.
64bit Processors: The computing standard.
Battlestar Galactica: Considered one of the greatest sci-fi series of all time.
Facebook: Continues to be the world’s leading social media platform by literally BILLIONS of users.
High Definition: HD only got even more HD.
iPhone: Set the standard for mobile smartphone form factor and function to this day 16 years later.
Possibly, now that we have much tighter integration between different chips using die-to-die interconnects like Apple's "UltraFusion" and AMD's "Infinity Fabric" to avoid the latency and microstutter issues that came with old-fashioned multi-GPU cards like the GTX 690 and Radeon HD 7990 XT.
As long as software can make proper use of the multiple processing units, I think multi-GPU cards have a chance to make a comeback... at least if anyone can actually afford the bloody things. Frankly, GPU pricing is a bit fucked at the moment even before we consider the idea of cards with multiple dies.