So I have a PowerColor Radeon HD4850 512MB, but in the chaos of moving house (twice!) I've managed to lose/destroy the box. Now, having seen some crazy deals on 4870s I'm thinking of upgrading. Would it be worth buying a 4870 512MB and crossfiring, or trying to sell the 4850 and buy a single 4870 1GB? Also, will not having the box seriously affect the selling price of my 4850? Thank you for any and all advice!

