Best sound card position?

[blahzicle]

About a month ago I purchased an Asus Xonar DGX, but because of my setup (gpu and wifi card) I thought I had to swap my gpu from the upper pcie slot to the lower one. I know people run sli configurations with little room in between for air space, but I like having room and decent air flow for my graphics card. That being said, my card obviously got hotter and I'm trying to rearrange things if I can.

I've attached a photo of what the setup is like now
http/imgur.com/BWS9uNg

mobo: Asus z87 plus
gpu: Asus DirectCU II gtx 780 OC
wifi: TP-Link TL-WDN4800
soundcard: Asus Xonar DGX

I have the following slots available:
2 x PCIe 3.0/2.0 x16 (x16 or dual x8)
1 x PCIe 2.0 x16 (x2 mode)
2 x PCIe 2.0 x1
2 x PCI

I'm not sure about EMI interference and I was also worried about having the sound card too close to my gpu for heat purposes. The sound card is pcie compatible but I'm not sure if that means I can put it in the other x16 slot. Any help is greatly appreciated!

Edit:
Kept doing research on my own but wasn't understanding some of the info I found, but came across this site http/techreport.com/review/23624/how-to-build-a-pc-the-tech-report-guide/9 and decided to give this configuration a try. Gonna test it now but still open to other suggestions.

 

[Mr Kagouris]

You can plug the sound card into a PCIe x16 slot too.

 

[blahzicle]

Yup, that's exactly what I did and it seems to be working great! I saw some info that said it would slow my gpu down to x8 speed (if I understood it correctly), but that doesn't seem to be the case. Sound is working great, gpu is still working great - everything is good so far. Thanks you so much!

 

[Mr Kagouris]

Plugging an expansion card into the second x16 slot will indeed make your GPU run at x8, although this wouldn't actually "slow down" your GPU. The third x16 slot (which I'm assuming you plugged the sound card into) doesn't share the same PCI lanes as the first two slots, so it doesn't affect them.