Datasheet figures next to each other, and the airflow balance, pressure verdict and case air heating that the fans in each box compute to behind that case's own front. Calculated with the CaseFlow model, not measured.
| BitFenix COL II | BitFenix P100 | |
|---|---|---|
| Form | ATX mid tower | ATX mid tower |
| Volume | 51.8 L | 52.1 L |
| Dimensions | 425 × 280 × 435 mm | 424 × 280 × 439 mm |
| Front | solid solid or glass front | solid solid or glass front |
| Fan mounts | front 3 × 120, top 3 × 120, rear 1 × 120, bottom 3 × 120 | front 3 × 120, rear 1 × 120, bottom 3 × 120 |
| Radiator support | front 360 mm, top 360 mm, rear 120 mm, bottom 360 mm | front 360 mm, rear 120 mm, bottom 360 mm |
| Dust filters | – | – |
| GPU length | 410 mm | 410 mm |
| Cooler height | 160 mm | 160 mm |
| Stock fans | none | none |
| Stock airflow, max rpm | – | – |
| Stock pressure verdict | ships without fans | ships without fans |
| Case air at 290 W | – | – |
| Stock fan noise | – | – |
| All mounts, reference fans | 234 in / 211 out CFM 6 / 4 mounts | 234 in / 53 out CFM 6 / 1 mounts |
With a reference pressure-optimized fan on every mount the COL II moves more air. Neither ships with fans, so only the mount capacity row compares. The pressure verdict describes the stock fan set, not the case: stronger or extra intake fans in the free mounts, or slower exhaust fans, turn a negative balance positive.
Neither ships with fans the model knows, so there is nothing to plot. Open them in CaseFlow and add fans.
Each stock fan contributes CFMmax · derate · rpm/rpmmax behind its wall's mounting class: filtered mesh
front and side mounts as dust filter, bottom as floor + filter, top and rear as open grille, solid and glass fronts as side-slit intake at
roughly half of a mesh front. Front, bottom and side blow in; top and rear blow out.
| Mounting | Airflow blades | Pressure-optimized |
|---|---|---|
| Open grille | 0.88 (0.80–0.95) | 0.88 (0.80–0.95) |
| Dust filter | 0.70 (0.60–0.80) | 0.78 (0.70–0.86) |
| Floor + filter | 0.64 (0.52–0.74) | 0.72 (0.62–0.80) |
| Solid or glass front | 0.50 (0.40–0.62) | 0.58 (0.48–0.68) |
Worst case sums intake at the low end of each band and exhaust at the high end; positive there means positive regardless of how the estimates fall. Case air: ΔT = 3.1 · W / throughput (m³/h), with an open-cooler GPU putting its full board power into the case air plus board, RAM and drives. Capacity puts a reference pressure-optimized fan on every mount at max rpm — 120 mm 60 CFM, 140 mm 75 CFM — a generic good fan, not a product.
Mount counts, radiator support and clearances are datasheet figures. Nothing here is measured; the same model runs in CaseFlow.