Tony Fernandes broke the club's transfer record to bring Samba to Loftus Road from Anzhi Makhachkala on deadline day, and the centre-half helped deliver a clean sheet two days later in a 0-0 draw with Norwich.
Rangers are currently six points adrift of safety with 13 games remaining, but Samba said: "I have seen for myself now we have enough to remain in this league."
A promising debut came despite a five-week idle period during the Russian close-season, and Samba knows his fitness still needs work.
"I'd only done five days of training after five weeks out before coming here," he told the club's official website.
"This is the English league and it is physical. It was a more intensive style of play than it was in Russia.
"To get a clean sheet against Norwich was pleasing but I was very disappointed to get a goalless draw as a win would have put us back among the chasing pack."