Chassis = case's make and model.
Considering you can operate a GT730 in your system, the GTX1050Ti would be a good candidate to swap over to. Mind you, with the current specs you have, I wouldn't expect stellar numbers(FPS) since you're on an aged platform. For 1080p gaming on Esports titles, you're going to be fine but for 1080p at high details, you're going to stutter. You could try and reduce the game details or the resolution or tinker with settings to get the most out of your system.