If you are worried about temps, don't be. Remember that there are people who run GXT 480s next to each other with less that a couple of millimetres of room and they stay sufficiently cool.
However if you do getting hissing or crackling in the sound from the xonar, try the EMI shield.
(you could always send the xonar DG back and get a xonar DGX which would go in the bottom pci e 1x slot, giving your GPU more room around the fan)
I am actually worried about temps and the hardware itself frying out! I shall get a more powerful fan for the case, so that cooling improves.
Your answer gives me the confidence to atleast set up the hardware! Best answer
Didn't get the Xonar DGX in India, that's why I went with the DG
how is your gpu temps ?
GPU runs at about 55-60 C while gaming ( resolution is 1366*768 , FPS 55-60) and about 35-40 C on normal usage.
There is a change of EMI (electro-magnetic interference) with the two pieces of hardware so close to each other which can possibly effect the sound card performance but I found this page that describes how to make an EMI shield http://www.overclock.net/t/571718/how-to-make-emi-shielding-for-your-sound-card
I would suggest trying the sound card as is at first, then making a shield if needed.
Hope it helps
I shall keep that in mind. I didn't know of EMI! Thanks