Right now it’s 2.5 I heard by next year will be 3.0 and 10x faster processor that is problem with hardware verses software if mother board can’t except newer hardware the newer software may not work due to the limitations of architecture design in that system. That why you can never keep up your old system without adding or replacing to match the new Technology. Another catch 22 for this future designs unless they find away to make it updatable and affordable.