I have been playing as lot with the Hwbot XTU benchmark lately.
Daily 24/7 - must be this one: http://hwbot.org/xtu/share/2113
Its not on the edge of stability, but as for heavy gaming, a little surfing, watching movies etc it seems to be ideal and the powerdraw is reasonable for the computer to be on 24/7.
Another candiate will be this http://hwbot.org/xtu/analyze/2393043 , but it seems to pull alot of power when gaming, so I am coming back to the first one so far.
I got 5 other specs for when it comes to benching ;-)