Raceroom says it requires 1024mb dedicated vram but I can run it on a intel i3 1005g1 with integrated uhd gfx at 1080p 60fps low-ish settings, same goes for AC.
Race 07/GTR2/Automobilista 1 can run higher gfx settings because they're older.
From what I understand the Integrated gfx share ram, so the more ram you have the more vram you get (up to a point) I stuck a 16gb ram stick in my laptop to give me a total of 20gb ram (4gb soldered onboard), so the integrated gpu shares half (10gb available), however I believe it only uses a maximum of 4096 dedicated.
Also you need to run your laptop in high performance mode so it uses all available ram & vram from the start of the process, you can find this under power options.
There's a few other little tweaks you can do to get games running better on a potato laptop but I'm only just relearning everything again myself.