Just days before throwing down at Dr. Dre's billionaire party -- Tyrese literally drove HOURS to Vegas with his pal The Game ... inside the world's first tricked-out $350,000 "Rolls Royce" van ... just to pick up a couple slices at the Bellagio.
Tyrese tells TMZ, he picked Game up Wednesday in L.A. and made the day trip in his brand new customized ride -- what he's calling the world's first ever "Rolls Royce Ghost Sprinter" van.
The whip's stacked too -- complete with several Apple TVs, a PlayStation 4, Xbox One, Mac Mini, custom Rolls rims and grill, crazy neon "Transformers" lights, a phone charger at each seat, Internet, and even a heated floor.
Tyrese says as soon as they grubbed down at Bellagio they immediately hightailed it back to L.A. Because, why not.
Game tells us, the carpet in the van was so nice, he didn't even bother to wear shoes -- "I made it to Vegas and all the way back in a fresh pair of white socks."