When in the editor I am getting some lag. It is so bad that when I mouse over something it is 1-2 seconds before it recognizes the mouse’s location.
My computer Specs
Intel Core i7 3820
Ram: 32GB
Nvidia GT 630 dual video cards
How can I increase performance
Well, your specs are similar to mine and should be more than enough for the editor on highest settings. I have a constant fps of 100+ and you shouldn’t lag either.
You can always try changing the settings: https://de45xmedrsdbp.cloudfront.net/blog/scalability_screen-770x644-1779705007.jpg just to see if you see any difference, but you certainly shouldn’t have to.
Other than that, probably obvious but, do you use the latest drivers for everything?
I’ve heard SLI can cause problems with some applications, I don’t know how severe or if it’s something that affects UE4 as I have never experienced them but you might want to at least try to deactivate one of your cards just to see if there is any difference.
I have tried updating everything and nothing changes.
Just to clarify, are you getting low frames-per-second, or are you getting lag?
Also, check your CPU usage while you have the program running.
It can be SLI causing this, or something running in the background, or the OS may need reinstalling.
Dual 630’s while your system has 32GB ram and entry sandy-e cpu?
Your GPU cards are holding your system back.
Blockquote NVIDIA GeForce 470 GTX or AMD Radeon 6870 HD series card or higher
Compare 630 and 470 GTX side by side (gogle gpu-z specs or NV site)
630 are low-end cards And is ~3 Times slower than 470 GTX
This is a reason for celebration. 
Enjoy your shopping!
It appears to be low fps because it is only unreal that lags. My computer is just fine with the engine open
The unreal website says that 400 series is the min so why would my 600 series lag?
Thanks i went back and looked and realized the mistake. Looks like im buying a new video card