I have bought dozens of refurb / open box cards from Newegg. Some come bad, so test them right away and within 15 days they will give a refund once you ship it back.
But I stay away from them now myself as the savings is not as good as it used to be and many of mine have died down the road. Even ones only occasionally used seemed to die after a year or so. Anyway, I figure about 1 out of every 4 (25%) of the refurbs I have bought from them have since died, which isn't a great track record IMO.
I'm not bashing Newegg at all though, I just don't trust the open box items anymore. I have a monsterous order history with them that has only been slowed in growth because of them now charging NJ sales tax. Otherwise they are top notch and taken care of me well when there has been a problem. If they are about the same price shipped to me, Newegg will always get my orders. But with tax, ZZF or others often blow them away in price to NJ.