An expansion in fabs that manufacture DRAM memory chips wouldn't necessitate any new construction work these days, because most were partially shut down last year and the year before that.
At the time, sales of memory were so low compared to supply that this was the only option left, besides letting chip prices fall to a disastrous level.
Now, though, demand is good (in comparison), and has been rising quickly, enough to fill almost all available production capacity.
Kingston, for instance, booked almost all of Nanya's chip supply lines.
Powertech Technology (PTI), Walton Advanced Engineering and Formosa Advanced Technologies (FATC) are or will soon be in similar positions.
Walton has Elpida (and by extension Micron) and Winbond Electronics as customers, while PTI makes chips for Elpida Memory and Powerchip Technology.