you can't SLI GT 1030s (or 1050s or 1060s), so it will not increase your gaming performance (could run more monitors though if youre trying to use 6 monitors for some reason)
There are multiple GTX 1050/ti's that would work in a small form factor build. so sell the 1030 and get a 1050, check if you power supply is strong enough for it though.
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