One month after the ExtremeTech article was released, in April 2012, an
EE Times article reported that TSMC would only be offering
one process at 20-nm. This was well down from their
four process offerings at 28nm three low-power and one high-performance.
TSMC initially planned to offer two 20-nm processes, presumably a high performance process and a low-power process.
But, after some development, TSMC determined that there was not a noticeable performance difference between the two 20-nm processes.
Each node can be further tweaked for high performance or low power, so you can have 28nm HP (High Performance for stuff like graphics cards) or 28nm LP (Low Power for stuff like phones) etc. So which one did they decide on? Well that was never really in doubt after the name was leaked 20-SoC. SoC stands for system on chip, i.e. the things you find in your smartphones.
20-SoC is not optimized for high-performance graphics chips and although both AMD and Nvidia are big customers of TSMCs, the industry has rapidly moved on to ultra-mobile products where
low power is much more desirable than
ultimate performance. More importantly, Apple is an awful lot bigger and has a lot more money than both AMD and Nvidia combined.
Lets see what TSMC says about their
20nm performance
TSMCs 20nm process technology can provide 30 percent higher speed, 1.9 times the density, or 25 percent less power than its 28nm technology. TSMC 20nm technology is the manufacturing process behind a wide array of applications that run the gamut from tablets and smartphones to desktops and servers.
Im sure you noticed the lack of mention of graphics but the important part is the performance. TSMC claims 30% higher speed, but thats compared to their
low-power 28nm process! Compared to their high-performance process it would barely be 10% faster, if anything. I believe TSMCs 28nm HP would likely be faster for graphics cards than their 20nm-SoC.
So TSMC will only have one 20nm process called 20-SoC and it will be tweaked specifically for ultra-mobile products. It took a while for this to sink in and nobody really believed it. With every new node comes new graphics chips, simple as that so something would be done to make 20nm viable for graphics surely?