If you'll add your system to the rigbuilder
, it will help us help you. I know a lot of your components are going to be generic, but having stuff like the part number for your motherboard easily visible in your signature would make it easy to figure out what generation PCIe slots you have. We do know that you have a PCIe x16 slot that your video card is in, & I'm assuming it's a Gen 3 slot, but it's just that, an assumption. Either way, you're only going to be running a single GPU, so whether it's gen 2 or 3 won't make a big enough difference in performance to worry about. PCIe connectors are backwards & forwards compatible. The worst that happens is you limit your available bandwidth.
Your PSU is not great
, but it should still work ok for the GPU ranges you're using or looking at. If you're wanting a GTX1060, I don't think you've got a lot to worry about. Sure, you're going to have similar heat issues to what you've had with your GTX960 (though a reference cooler will be beneficial if you stay in the OEM Dell case), but nothing in your system is going to ruin your GPU.
I could be wrong (someone please correct me if so), but I'm assuming any discussion of motherboard VRMs & heatsinks is in regards to CPU overclocking, as the GPU has its own VRMs independent of your motherboard.