Thanks both
I'd would use smoky & not rose quartz for absorbing EMFs. Several ways you can do it, so you are right to experiment. You can wear a piece of smoky quartz as jewellery and keep it well cleansed, or place a chunk between you and the PC, or tape a piece to the PC remembering to cleanse and rest it. It's good to use two pieces in rotation like this.
I have a EMF meter which is great for detecting hotspots, as computers don't generate EMFs evenly. If you are sensitive it may be worth the investment to check your place out. There are some very reasonably priced ones available. Also beware mobile phones and cordless phones as these are really high producers of EMFs.