Lian Li A3-mATX Front PSU Bracket Height vs. GPU Length Trade-Off
The Lian Li A3-mATX is a modular 26.3-liter case designed in collaboration with DAN Cases. It features a multi-position front power supply bracket. Adjusting the bracket height directly dictates the maximum allowable GPU length and top AIO radiator compatibility.
Dimensional Matrix & Bracket Position Trade-Offs
The table below details physical clearance limits across the front PSU bracket height settings when paired with a 140 mm deep ATX power supply like the Seasonic Focus GX-850 ATX 3.0 power supply:
| Bracket Position | Max Allowable GPU Length | Top Radiator Allowance | 140mm ATX PSU Impact State |
|---|---|---|---|
| Position F1 (Highest) | 415.0 mm Max Clearance | Side Fan Only / No Top 360mm Fan 1 | PASSED for 400mm GPUs / Blocks Top Front Fan |
| Position F2 (Middle) | 334.0 mm Max Clearance | Top 360mm AIO Allowed | PASSED for GPUs <= 334mm / Full Top Radiator |
| Position F3 (Lowest) | 334.0 mm Max Clearance | Top 360mm Push-Pull Allowed | Modular Cables Extend Into GPU Tail Space |
The Bracket Height Dilemma
The front PSU bracket in the Lian Li A3-mATX supports 4 vertical mounting slots (labeled F1 through F3 for ATX power supplies). Adjusting bracket height creates a direct trade-off between top cooling clearance and front GPU length space:
- Position F1 (Highest Setting): Shifts the PSU cage up near the roof panel. This maximizes horizontal GPU clearance to 415 mm, easily accommodating extra-long graphics cards. However, the top of the PSU frame blocks the front fan mount of a top 360mm AIO radiator.
- Position F2 / F2.5 (Middle Settings): Lowers the PSU cage to clear top 360mm AIO radiators. However, lowering the PSU cage causes modular cable connectors to hang into the GPU clearance corridor, reducing max GPU length capacity to 334 mm.
Real-World GPU & Cooling Synergy
When installing cards like the PNY RTX 4070 Ti Super VERTO (measuring 305.1 mm in length), review our PNY RTX 4070 Ti Super in Lian Li A3-mATX fitment guide. The 305.1 mm card length allows setting the PSU bracket to Position F2, enabling simultaneous compatibility with a 305.1 mm GPU and a top 360mm AIO liquid cooler.
If air cooling is preferred, the A3-mATX provides 165 mm of CPU cooler height clearance. This easily accommodates large dual-tower heatsinks like DeepCool AK620 air cooler height clearance targets, allowing the PSU bracket to remain in Position F1 for maximum GPU length flexibility.
Builder Summary
- Position F1 (Highest): Enables 415 mm GPU length allowance; restricts top 360mm AIO front fan space.
- Position F2 (Middle): Enables top 360mm AIO installation; limits max GPU length to 334 mm.
- Recommended Pairing: Combine compact 140 mm ATX PSUs with GPUs under 334 mm to achieve simultaneous top 360mm AIO cooling and clean cable routing.