Dwight Howard had the most games by a player younger than 20 with 5+ rebounds, with 96 games.

Interpreted as:

most 5 or more rebound regular-season games before turning 20 years old by a player

	NAME	GP	REB	MPG	PPG	RPG	APG	SPG	BPG	FGM	FGA	FG%	3PM	3PA	3P%	FTM	FTA	FT%	TS%	OREB	DREB	TPG	MIN	PTS	AST	STL	BLK	TOV	PF	+/-
1	Dwight Howard D. Howard	96	1,046	33.4	12.6	10.9	1.0	1.0	1.7	4.5	8.9	50.9	0.0	0.0	0.0	3.6	5.4	65.6	55.9	3.6	7.3	2.1	3,210	1,213	97	92	160	198	290	-188
2	LeBron James L. James	74	541	40.9	23.4	7.3	6.3	2.0	0.8	8.8	19.5	45.0	0.9	2.7	33.0	4.9	6.5	75.3	52.2	1.6	5.7	3.4	3,023	1,730	469	148	59	252	141	+217
3	Jalen Duren J. Duren	63	644	26.6	10.3	10.2	1.4	0.7	0.8	4.4	6.8	64.7	0.0	0.0	0.0	1.5	2.3	64.3	65.8	3.8	6.4	1.6	1,677	650	91	45	53	98	182	-238
4	Jabari Smith Jr. J. Smith Jr.	62	517	31.7	13.3	8.3	1.3	0.6	1.0	4.8	11.7	40.9	1.6	5.1	30.7	2.2	2.8	77.7	51.5	1.8	6.5	1.3	1,964	825	83	36	64	81	174	-395
5	Tracy McGrady T. McGrady	60	437	25.6	11.0	7.3	2.5	1.1	1.4	4.2	9.2	45.1	0.3	0.8	32.0	2.4	3.3	72.9	51.5	3.2	4.1	1.8	1,538	661	147	63	86	105	119	-142
6	Josh Smith J. Smith	58	463	31.1	11.2	8.0	1.9	0.8	2.2	4.1	9.4	43.6	0.1	0.4	18.2	2.9	4.0	71.6	49.8	2.6	5.3	2.2	1,805	648	110	48	127	127	139	-278
7	Andrew Bynum A. Bynum	57	433	24.0	8.4	7.6	1.2	0.2	1.8	3.2	5.9	54.0	0.0	0.0	0.0	2.0	3.1	64.9	57.6	2.1	5.5	1.5	1,369	479	66	10	100	86	172	-14
8	Carmelo Anthony C. Anthony	55	416	38.1	21.9	7.6	3.0	1.4	0.5	7.9	18.5	42.7	0.9	2.7	32.0	5.3	6.9	76.5	50.9	2.8	4.8	3.1	2,094	1,207	165	76	26	171	157	+114
9	Kevin Garnett K. Garnett	52	429	33.4	12.8	8.3	2.1	1.2	2.0	5.5	11.0	50.2	0.1	0.4	26.3	1.7	2.4	69.4	53.1	2.7	5.6	1.5	1,739	667	109	63	106	79	134
10	Michael Kidd-Gilchrist M. Kidd-Gilchrist	51	379	27.8	10.6	7.4	1.5	0.7	0.9	4.2	8.7	48.0	0.0	0.1	33.3	2.2	3.0	74.8	52.9	2.2	5.2	1.4	1,420	542	78	37	47	73	117	-120
11	Darius Miles D. Miles	51	385	29.6	10.9	7.5	1.6	0.6	1.8	4.5	9.0	50.7	0.0	0.3	7.1	1.8	3.5	51.7	51.9	2.1	5.5	2.0	1,512	557	82	33	92	101	134	+86
12	Isaiah Stewart I. Stewart	50	405	22.9	8.9	8.1	1.0	0.6	1.4	3.8	6.8	55.6	0.3	1.0	28.8	1.0	1.4	69.4	59.5	2.9	5.2	1.0	1,147	445	50	30	70	52	134	+1
13	Chris Bosh C. Bosh	50	420	35.4	12.1	8.4	1.1	0.8	1.5	4.6	10.1	45.6	0.1	0.2	37.5	2.8	4.2	67.0	50.6	2.9	5.5	1.4	1,770	607	55	40	73	70	148	-116
14	Alex Sarr A. Sarr	49	376	27.6	13.6	7.7	2.4	0.7	1.6	5.1	12.5	40.6	1.6	5.0	32.5	1.9	2.8	66.4	49.5	2.1	5.6	1.8	1,353	668	120	33	79	88	111	-335
15	Luka Dončić L. Dončić	49	393	32.5	20.9	8.0	5.8	1.0	0.3	6.9	16.1	42.6	2.3	7.0	33.2	4.8	6.5	74.0	55.0	1.1	6.9	3.4	1,593	1,022	282	47	14	168	94	-5
16	Josh Giddey J. Giddey	47	402	31.7	12.2	8.6	6.3	1.0	0.4	5.1	12.5	40.8	1.0	3.9	25.4	1.0	1.4	72.7	46.5	2.0	6.5	3.2	1,491	572	297	46	17	150	75	-258
17	Giannis Antetokounmpo G. Antetokounmpo	46	321	29.4	10.2	7.0	2.5	0.8	1.0	3.6	7.4	48.2	0.4	1.3	33.9	2.7	3.7	71.3	56.6	1.7	5.3	1.8	1,351	470	115	36	44	81	112	-10
18	Andre Drummond A. Drummond	45	418	22.4	8.8	9.3	0.5	1.1	1.7	3.8	6.4	59.4	0.0	0.0	0.0	1.2	3.2	37.1	56.3	3.6	5.7	1.0	1,007	395	21	48	75	46	115	-20
19	Derrick Favors D. Favors	45	321	21.6	7.8	7.1	0.7	0.4	1.1	3.0	6.0	50.4	0.0	0.0		1.8	2.8	64.5	54.3	3.0	4.2	1.0	972	350	30	19	48	46	143	-98
20	Marvin Williams M. Williams	44	291	26.4	9.4	6.6	1.0	0.7	0.4	3.2	7.3	43.4	0.2	0.7	30.0	2.9	3.9	72.8	52.1	2.0	4.6	1.3	1,162	413	42	31	16	56	130	-51
21	Eddie Griffin E. Griffin	43	334	31.7	11.1	7.8	0.7	0.3	2.3	4.2	11.0	38.4	1.4	4.3	33.9	1.2	1.7	74.6	47.4	2.2	5.6	0.9	1,363	479	31	12	101	38	73	-103
22	Jarrett Allen J. Allen	42	304	22.6	10.1	7.2	0.8	0.3	1.4	4.0	6.6	60.4	0.1	0.2	30.0	2.1	2.7	77.7	65.1	2.6	4.6	1.1	949	426	32	13	57	47	97	-73
23	Alperen Sengun A. Sengun	40	300	23.4	11.1	7.5	3.0	0.9	1.1	4.1	8.6	48.2	0.4	1.8	24.3	2.4	3.4	70.4	55.1	2.6	4.9	2.3	936	442	121	37	42	92	121	-166
24	Anthony Davis A. Davis	39	356	29.2	13.6	9.1	1.0	1.1	1.9	5.7	11.2	51.3	0.0	0.2	0.0	2.2	3.2	68.3	54.2	2.8	6.4	1.5	1,139	530	40	42	73	60	82	-76
25	Luol Deng L. Deng	39	269	30.4	13.5	6.9	2.4	0.8	0.6	5.2	12.0	43.7	0.6	2.2	29.4	2.4	3.2	73.0	50.2	2.1	4.8	2.1	1,187	525	93	33	22	81	67	+186