btw i can switch between half-size and full-size WHILE in fullscreen mode with F5. If it works for you it might be an alternative to playing in window mode
!I never realised you can do this for RM.
Well, it kinda works (half size full screen mode) is smooth and feels "correct" in term of size. It'd better if I can manually change the resolution for the full screen, but this would work methinks; Thanks dude!

Time to play with different resolutions to see if I could make it bigger.
PS I am still open to any alternative solution/tips (if any).
EDIT
Can someone tell me what these two means :
1. Higher Refresh rate (my setting can't go above/less than 60; is this bad?)
2. V-Sync Value? (Timing setting Horizontal Sync and Vertical sync width/polarity)
for the 2nd; the default value is H:32 V:6
Tried messing with the V value but nothing seems to change :\ (so I revert it back to auto). Does having high value (like I try 32) mess my computer?