Thanks Krakan!

So after more research it looks like I can only fit one Titan card in there using a 90 degree PCI adaptor. The downside is that the other PCI slots will be blocked :/

It should still be a pretty sweet system, 3.8GHz, 32GB RAM & 6GB GPU, for less than $3k.

Either that or get a new case. As unreasonable as it sounds, aesthetics are as important to me in this build as the guts themselves.

Haha, I'm comfortable doing the build once I have the parts but I'm by no means an expert. This build is kinda complicated and I'm honestly not up on the latest tech. I'm not sure what parts'll fit for the most extreme performance.

The last system I built was in 2004 and sounded like a jumbo jet! 

Tentatively I would say this mobo will fit.

http://ca.gigabyte.com/products/product-page.aspx?pid=4049#sp

EDIT cool, I think your recomendation would fit as well.

But I'm planning to replace all parts, which means getting a new motherboard that can support a better CPU. The current motherboard has got to go.

Do you have any mobo/cpu suggestions for the size of my case?

Do you mean the size available to the new/replacement motherboard is insufficient?

I'm not sure about the standoffs, I haven't gotten that deep yet...

FaustArp, cool thanks. I just posted the motherboard to illustrate the dimensions. I'll need a new one for sure. Have any suggestions?

MuD3, Cool man, those are awesome leads.

This is my current motherboard, which I believe is a fairly decent size, 11.5" (29.2 cm) x 11" (27.9 cm) http://h10025.www1.hp.com/ewfrf/wc/document?cc=uk&lc=en&dlc=en&docname=c01690297

I am wondering if I can house all of my GPU's externally in one of these: http://www.cubix.com/gpu-xpander-rackmount

Or is there any reason I need one internally? My wishlist consists of dual Nvidia Titan cards.

Perhaps I could run a secondary powersupply externally as well?

5-7k.

I understand that using this old case isn't the most straightforward or best way to go, but I am super passionate about building a PC that I can be proud of and care about.

Anyone think it's possible?