The E3-1505M does support ECC, not particularly hard to believe that it's a supported feature now. I believe ECC overhead is around 12.5% (9 bits instead of 8)

The E3-1505M does support ECC, not particularly hard to believe that it's a supported feature now. I believe ECC overhead is around 12.5% (9 bits instead of 8) for the memory system. However I don't know what percent of power the memory system usually takes. Seems like about half the power is required for a 3200x1800 display + touchscreen. The XPS 13 goes from 22 hours to 12 hours when you switch from 3200x1800 touch to 1080 non-touch. Of course 1080P screens are lower power, but not zero. Of the rest the CPU takes a fair amount. As a guess I'd say a 15% increase in memory power might decrease the runtime by 20 minutes.