Make sure that your Intel Integrated Graphics drivers are also up to date. I believe they are around version 15 now IIRC.
If you know that the GPU is actually being used this falls more into a performance question rather than a question for switching from integrated to card GPUs. This would be better served as asking as a separate question on the AnswerHub.
To narrow down any performance issues you can start by profiling the GPU and CPU for your games performance.
If you’re not familiar withe process of profiling you can start by having a look at this Support Stream and our documentation linked below: