Ahh even so I'd go about upgrading that RAM, the recommended amount of ram is 2GB minimum per client so you're pushing it even with your current setup. I'd go for 40GB for 16 clients, I also don't see a 4 core cpu being able to support 16 clients and anyone I know who runs 10+ clients runs at least SLI 1080s but I'm not sure if that's necessary.