I can't speak for the X99 Sabertooth, but I think the Asus X99-E WS ("workstation") motherboard would be a better choice for a machine meant to operate 24/7. The WS is designed for server-grade reliability, the Sabertooth is designed to appeal to gamers. Stability is not really assured when you overclock - regardless of mobo model - but the WS uses much the same hardware/firmware components (including the Asus X99 OC Socket) that can be found on the ROG enthusiast mobos.
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