x16/x16 vs x8/x8

Question

I am considering purchasing an LGA1155 board but dual GPUs they only run at x8/x8.

From my research it seems that you lose about 1-3% tops when running at 2500*1600 but a lot more when running games over multiple monitors / bigger resolutions.

My setup will be to only ever play games on my 30" (2500*1600) but I will have up to 4 additional monitors on at the same time, just not rendering the game. Will this cause more performance loss. Also, all the tests I could find were on last generation GPUs and the most current will use even more bandwidth?

Realistically, with multiple monitors but a game running at 2500*1600 using two new generation GPUs what performance hit should I expect to take with x8/x8 vs x16/x16?

Answer 1

It all depends. If you're using two graphics cards that will each barely perform better than 8x then you will basically have full potential from the setup. However, if you have one very good graphics card that will perform at a full 16x and puts it to full use, then you will get similar performance. It would really bank on the video cards that you'll be using. Get one or two that will best match your motherboard and system specs. Two decent GPUs running at 8x and using the bandwidth to it's full potential will be your more economical setup. However, one GPU at 16x would probably be rather expensive if purchasing one that would run at the full bandwidth of 16x.