The Phanteks XT Pro Ultra wins in 3 out of 8 comparable specs. Its biggest advantage is Max PSU Length (19% better).
H9 Flow wins in 2 specs (2.5" Bays: 33% better).
Recommendation
Choose XT Pro Ultra if you want the best overall performance — especially max psu length.
Choose H9 Flow if 2.5" bays matters more to you.
| Spec | NZXTH9 Flow | PhanteksXT Pro Ultra |
|---|---|---|
| Design | ||
| Type | ATX Mid Tower | ATX Mid Tower |
| Side Panel | Tempered Glass | Tempered Glass |
| Weight | 10.2 | 10.5 |
| Compatibility | ||
| Max GPU Length | 435 mm | 435 mm |
| Max Cooler Height | 165 mm | 181 mm+10% |
| Max PSU Length | 185 mm | 220 mm+19% |
| Max Radiator | ||
| 360 mm |
| 420 mm+17% |
| Motherboard Support | ATX, Micro ATX, Mini ITX | ATX, EATX, Micro ATX, Mini ITX |
| Cooling | ||
| Included Fans | 4 | 4 |
| Storage | ||
| 2.5" Bays | 4+33% | 3 |
| 3.5" Bays | 2 | 2 |
| I/O | ||
| Front I/O | 1x USB-C, 2x USB-A 3.0, Audio | 1x USB-C, 2x USB-A 3.0, Audio |
| Price | ||
| MSRP | $165−3% | $170 |
| Release Date | Jan 2023 | Jul 2024 |
