Tons of multitasking - no problem.  Latest games - Assetto Corsa Competizione,  IL2 Sturmovik, Fallen Jedi, New Microsoft Flight Sim...  All video parameters on maxed-out levels - no problems.  No problems with heat on this baby - six 120mm fans!!  Granted, that creates some rushing air noise, especially if you set it on the table/desk, but with headphones or good speakers who cares!Haven't yet tried to add another hard disk, but I suspect it has been set up to make that easy!Best advice if you are going to buy - Get a big new HD or 4K monitor!!