I have a concert project coming up which has 7 cameras. I have PP CC15 on a 2013 MBP which I use every day to edit video with a couple of video tracks. I also have a 2008 8-core Mac Pro with 16 gbs of memory and aRAID 5 box but with stock video card. I'm wondering if its better to upgrade my MacPro with a new gfx card and more ram or should I upgrade to something that can handle the multiple video streams. Of course $$ is a factor.
I have 32GB (4x 8GB) of 133DDR3 ECC memory sticks from my former 2008 MAC Pro 2,1. e-mail me if you want to purchase them. You can upgrade to 32GB DDR3 on the MAC Pro 2,1. Just make sure the sticks are all the same speed and capacity.
I would upgrade your graphics card to something like an INVIDIA GEforce GFX 660Ti which has either 2GB or 3GB of memory and over 1,000 CUDA cores. This card is going into my 2012, MAC Pro 5,1 tower next week. The more memory and CUDA cores you have to work with, the faster your processing, rendering, transcoding and such. The GTX 660Ti card is a balance of price, speed, CUDA cores and memory. Remember that you have to turn on Mercury Playback Engine Processor under Project/Settings/General tab.