UE4 very laggy, why?

@ - you’ll run the editor, but the graphics card is a little on the weak side since it’s a low-end mobile model rather than a performance or enthusiast set.

It’s not “medium-end”, it’s a machine built for web browsing and document editing and unsuitable for the job. The CPU is a little on the lower-end side, but the real killer is the Intel Iris GPU - it’s just plain unsuitable for modern graphics engines (it’s comparable to a Geforce 8 series from 10 years ago). This isn’t “optimisation problems”, this is simply a case of hardware not being up to the task.

Also, I don’t get why you’ve bumped this thread from months ago, but it seems like you have an axe to grind.