The be quiet! Dark Base Pro 901 wins in 6 out of 8 comparable specs, with 1 tie. Its biggest advantage is 2.5" Bays (150% better).
4000D RS Frame wins in 1 spec (MSRP: 59% better).
Recommendation
Choose Dark Base Pro 901 if you want the best overall performance — especially 2.5" bays.
Choose 4000D RS Frame if msrp matters more to you.
AI Versus Verdict
The be quiet! Dark Base Pro 901 is the objective winner of this comparison, securing a lead in six out of eight measured specifications. Its most significant advantage over the competition is its storage capacity, offering 150% more 2.5" drive bays. This superior hardware configuration makes it the more versatile choice for users requiring extensive internal component support and expansion options compared to the alternative.
The Corsair 4000D RS Frame is the recommended choice for budget-conscious builders, as it holds a 59% advantage in MSRP. Users prioritizing cost efficiency should select this model for their system. Conversely, those who require the high-capacity storage capabilities provided by the be quiet! Dark Base Pro 901 should opt for that unit to maximize their build's internal drive potential.
Generated by Gemini from the objective spec comparison above. AI advice is a summary, not a benchmark — always verify critical purchases.