Buying Guide
The Best Micro-ATX Cases
Six Micro-ATX cases compared on GPU clearance, radiator support, volume and power supply options, from a 21L box to a 435mm-GPU tower.
By Alex Morgan, PC Hardware Editor
12 min read6 products evaluated

Micro-ATX cases save desk space and cost less than most mid-towers, and the best of them now take full-length graphics cards and 360mm radiators. The trade-offs are power supply format, cooler height and fan count.
We compared six Micro-ATX cases on listed clearances, radiator support, volume and power supply options. The comparison is research-based, taken from maker specifications, not from builds of our own.
Quick Picks
Which of the 6 picks to look at first. Tap a name for the full analysis.

Best Micro-ATX Case
Lian Li A3-mATX (Wood)415mm GPU room and a 360mm radiator in 26.3L.
Best for: A compact gaming build with a large graphics card.
Check price for Lian Li A3-mATX (Wood) on Amazon (opens in a new tab)
Most GPU Room
JONSBO D33435mm of GPU clearance with front USB-C.
Best for: The longest graphics cards in a Micro-ATX build.
Check price for JONSBO D33 on Amazon (opens in a new tab)
Smallest Pick
Lian Li B4-mATX (Mesh)A 21.3L volume with two fans included.
Best for: Builders who want the smallest Micro-ATX footprint.
Check price for Lian Li B4-mATX (Mesh) on Amazon (opens in a new tab)
Best Mesh Airflow
ASUS Prime AP201Mesh panels with over 57,000 holes.
Best for: Airflow-first compact builds.
Check price for ASUS Prime AP201 on Amazon (opens in a new tab)
Best for ATX Power Supplies
JONSBO D31 MESHATX or SFX units up to 220mm long.
Best for: Builders reusing a long ATX power supply.
Check price for JONSBO D31 MESH on Amazon (opens in a new tab)
Best Glass Micro-ATX
CORSAIR 2800X RS-RA glass side and front with three reverse-rotor fans.
Best for: A compact showcase build.
Check price for CORSAIR 2800X RS-R on Amazon (opens in a new tab)
Our Picks
Best Micro-ATX Case1 of 6
Lian Li A3-mATX (Wood)
The A3-mATX fits a 415mm graphics card and a 360mm radiator into 26.3 litres, and the power supply can sit at the front or the side.
Best for
- A compact gaming build with a large graphics card.
Skip if
- Skip it if you need to know its PSU length limit before buying; the maker doesn't publish one.
Why we like it
ATX, SFX and SFX-L units are all listed. On GPU clearance it sits mid-pack at 415mm: the D33 comes in at 435mm, and the Prime AP201 comes in at 338mm. On volume it sits mid-pack at 26.3L: the B4-mATX comes in at 21.3L, and the Prime AP201 comes in at 33L.
You also get mounts for up to ten 120mm fans, a wood front with steel mesh panels and four expansion slots. GPU limit in the A3-mATX: 415mm, before front fans. The A3-mATX takes 360mm radiators; mind RAM height.
Boards: mATX, ITX. When we checked, only the 2800X RS-R and cheaper picks cost less, and the Prime AP201 cost more.
Key specs
- Max GPU length
- 415mm
- Largest radiator
- 360mm
- Volume
- 26.3L
- Motherboards
- mATX, ITX
- PSU type
- ATX, SFX or SFX-L
Pros
- Room for graphics cards up to 415mm long
- Fits a 360mm radiator
- Front or side PSU mounting
- Mounts for up to ten 120mm fans
Cons
- No published PSU length limit
- Costs more than the B4-mATX at the time of writing
The catch
If you want a confirmed CPU cooler clearance, look to the D33 instead: it comes in at 172mm, while this one gives no figure.
Most GPU Room2 of 6
JONSBO D33
The D33 offers 435mm of GPU room and a 172mm cooler limit, the most generous figures in this Micro-ATX group.
Best for
- The longest graphics cards in a Micro-ATX build.
Skip if
- Pass if a published PSU length limit matters; this one has none.
Why we like it
It also takes back-connect mATX BTF boards and has a front USB-C port. Nothing else here matches its 435mm GPU clearance; the A3-mATX comes closest at 415mm. It also comes with nine fan positions, a magnetic front grille and two 3.5-inch and two 2.5-inch drive bays.
GPU limit in the D33: 435mm, before front fans. The D33 takes 360mm radiators; mind RAM height. Boards: Micro-ATX, Mini-ITX, mATX BTF.
Only the Prime AP201 came close to it on price at the time of writing; it cost the most of the 6 picks. There is no published PSU length limit figure, whereas the D31 Mesh comes in at 220mm.
Key specs
- Max GPU length
- 435mm
- Max CPU cooler height
- 172mm
- Largest radiator
- 360mm
- Motherboards
- Micro-ATX, Mini-ITX, mATX BTF
- PSU type
- ATX or SFX
- Front USB-C
- Yes
Pros
- Room for graphics cards up to 435mm long
- Takes tower air coolers up to 172mm tall
- Fits a 360mm radiator
- A front USB-C port
Cons
- No published PSU length limit
- No published volume
- Costs more than the B4-mATX at the time of writing
Smallest Pick3 of 6
Lian Li B4-mATX (Mesh)
The B4-mATX is the smallest case here at 21.3 litres and still takes a 358mm graphics card.
Best for
- Builders who want the smallest Micro-ATX footprint.
Skip if
- Worth skipping when power supplies are limited to 140mm long is a problem.
Why we like it
Choosing an SFX power supply frees room for a 360mm AIO; an ATX unit must be 140mm or shorter. Its 358mm GPU clearance ranks fourth of 5 here, behind the D33 (435mm) and ahead of the Prime AP201 (338mm). On PSU length limit it trails the group at 140mm, while the D31 Mesh comes in at 220mm.
Nothing else here matches its 21.3L volume; the A3-mATX comes closest at 26.3L. MATX motherboards is unique to it among these picks, while the 2800X RS-R uses micro-ATX motherboards. You also get two slim 120mm fans and a 360mm AIO when paired with an SFX PSU.
GPU limit in the B4-mATX: 358mm, before front fans. The B4-mATX takes 360mm radiators; mind RAM height. 140mm is the B4-mATX's PSU length cap.
Boards: mATX. It undercut the D31 Mesh and every other pick on price at the time of writing.
Key specs
- Max GPU length
- 358mm
- Largest radiator
- 360mm
- Max PSU length
- 140mm
- Volume
- 21.3L
- Fans included
- 2
- Motherboards
- mATX
- PSU type
- SFX, or ATX up to 140mm
Pros
- Fits a 360mm radiator
- A compact 21.3L footprint
- Two slim 120mm fans
- 360mm AIO when paired with an SFX PSU
Cons
- Power supplies are limited to 140mm long
- PSU length limit trails the D31 Mesh (220mm)
The catch
The maker doesn't give its CPU cooler clearance; if that figure matters, the D33 comes in at 172mm.
Best Mesh Airflow4 of 6
ASUS Prime AP201
The Prime AP201 wraps a 33-litre frame in fine mesh for airflow on every side.
Best for
- Airflow-first compact builds.
Skip if
- Skip it if GPU clearance matters most to you; the D33 offers 435mm.
Why we like it
It takes 338mm graphics cards and a 360mm radiator, with a 32mm gap behind the tray for cables. Mesh panels with over 57,000 holes keep airflow high, and it supports 280mm and 360mm radiators with up to six fans. It is a compact Micro-ATX case.
Its compact Micro-ATX body suits a small desk without giving up a 360mm radiator. On GPU clearance it trails the group at 338mm, while the D33 comes in at 435mm. Its 180mm PSU length limit ranks second of 3 here, behind the D31 Mesh (220mm) and ahead of the B4-mATX (140mm).
On volume it trails the group at 33L, while the B4-mATX comes in at 21.3L. Like the 2800X RS-R, it has micro-ATX motherboards, while the B4-mATX uses mATX motherboards. GPU limit in the Prime AP201: 338mm, before front fans.
The Prime AP201 takes 360mm radiators; mind RAM height. 180mm is the Prime AP201's PSU length cap.
Key specs
- Max GPU length
- 338mm
- Largest radiator
- 360mm
- Max PSU length
- 180mm
- Volume
- 33L
- Motherboards
- Micro-ATX
Pros
- Fits a 360mm radiator
- Mesh panels with over 57,000 1.5mm holes
- 32mm cable gap behind the tray
- Mounts for up to six fans
Cons
- GPU clearance trails the D33 (435mm)
- Volume trails the B4-mATX (21.3L)
- Costs more than the B4-mATX at the time of writing
The catch
GPU clearance is its weakest area, and the D33 covers it better at 435mm.
Best for ATX Power Supplies5 of 6
JONSBO D31 MESH
The D31 Mesh takes ATX or SFX power supplies up to 220mm long and a 168mm tower cooler.
Best for
- Builders reusing a long ATX power supply.
Skip if
- Its GPU clearance is not published, which rules it out if you need that number.
Why we like it
Its GPU limit runs from 330mm to 400mm depending on how you lay out the case. On PSU length limit it leads this guide at 220mm, ahead of the Prime AP201 (180mm). It also offers outer dimensions of 205 x 363 x 452mm.
Confirm GPU length for the D31 Mesh with its maker. 220mm is the D31 Mesh's PSU length cap. Boards: mATX, ITX.
On price it sat second of 6, between the cheaper B4-mATX and the pricier 2800X RS-R, at the time of writing. The maker doesn't give its GPU clearance; if that figure matters, the D33 comes in at 435mm.
Key specs
- Max CPU cooler height
- 168mm
- Max PSU length
- 220mm
- Motherboards
- mATX, ITX
- PSU type
- ATX or SFX
Pros
- Takes tower air coolers up to 168mm tall
- GPU room of 330mm to 400mm depending on layout
- Mesh front
- Outer dimensions of 205 x 363 x 452mm
Cons
- No published GPU clearance
- No published largest radiator size
- No published volume
Best Glass Micro-ATX6 of 6
CORSAIR 2800X RS-R
The 2800X RS-R puts three reverse-rotor intake fans in its side panel so the lit side faces the glass.
Best for
- A compact showcase build.
Skip if
- Its largest radiator size is not published, which rules it out if you need that number.
Why we like it
It has 410mm of GPU room in a Micro-ATX footprint. Wraparound glass shows off the build, and three reverse-rotor fans in the side panel pull air in. It suits a showcase build.
Its 410mm GPU clearance ranks third of 5 here, behind the D33 (435mm) and ahead of the Prime AP201 (338mm). It shares micro-ATX motherboards with the Prime AP201; the B4-mATX goes with mATX motherboards. It also offers PWM and ARGB fan headers.
GPU limit in the 2800X RS-R: 410mm, before front fans. On price it sat third of 6, between the cheaper D31 Mesh and the pricier A3-mATX, at the time of writing. The maker doesn't give its CPU cooler clearance; if that figure matters, the D33 comes in at 172mm.
Key specs
- Max GPU length
- 410mm
- Fans included
- 3
- Motherboards
- Micro-ATX
- Glass
- Glass side and front
Pros
- Room for graphics cards up to 410mm long
- 3 fans included
- Glass side and front
- Three reverse-rotor RS120-R intake fans in the side panel
Cons
- No published largest radiator size
- No published PSU length limit
- No published volume
How We Chose These Micro-ATX Cases
Alex Morgan compared the manufacturer specifications, connectivity, warranty terms and compatibility of every pick. Figures come from the makers unless a third-party source is named; we did not test these products ourselves.

- What we compared
- We set side by side six cases on GPU clearance, CPU cooler clearance, largest radiator size and PSU length limit from manufacturer specifications. We did not test them in-house, and GPU clearance and CPU cooler clearance are missing for at least one pick.
- The shared baseline
- All 6, from the A3-mATX to the 2800X RS-R, state motherboards.
- Where the specs have gaps
- The D31 Mesh gives no GPU clearance; the A3-mATX, the B4-mATX, the Prime AP201 and the 2800X RS-R give no CPU cooler clearance.
- Price range
- At our last check the picks ran from the B4-mATX ($50 to $100) to the D33 ($100 to $150).
What to Look for in a Micro-ATX Case
Key buying criteria so you get the right fit the first time.
GPU clearance
Across these 5 picks GPU clearance spans 338mm (the Prime AP201) to 435mm (the D33). For less, the A3-mATX is the runner-up at 415mm ($50 to $100 tier). The D31 Mesh gives no GPU clearance figure, so 5 of 6 picks are compared here.
How much PSU length limit you need
Here PSU length limit runs from 140mm on the B4-mATX to 220mm on the D31 Mesh, a 57% spread. Start with the D31 Mesh if PSU length limit decides it. The A3-mATX, the D33 and the 2800X RS-R give no PSU length limit figure, so 3 of 6 picks are compared here.

Cable management behind the motherboard tray of a PC case Volume across these picks
Here volume runs from 33L on the Prime AP201 to 21.3L on the B4-mATX, a 35% spread. The B4-mATX is the pick for volume. The D33, the D31 Mesh and the 2800X RS-R give no volume figure, so 3 of 6 picks are compared here.
Fit and compatibility
GPU limit in the A3-mATX: 415mm, before front fans. GPU limit in the D33: 435mm, before front fans. GPU limit in the B4-mATX: 358mm, before front fans.

A case interior with a tower cooler and a graphics card installed Features beyond the spec table
The Prime AP201: a 32mm cable gap behind the tray. The D31 Mesh: a mesh front. The 2800X RS-R: PWM and ARGB fan headers.
How to Choose a Micro-ATX Case
By priority
| Priority | Consider | Why |
|---|---|---|
| A compact gaming build with a large graphics card | A3-mATX | 415mm GPU room and a 360mm radiator in 26.3L |
| The longest graphics cards in a Micro-ATX build | D33 | 435mm of GPU clearance with front USB-C |
| Builders who want the smallest Micro-ATX footprint | B4-mATX | A 21.3L volume with two fans included |
| Airflow-first compact builds | Prime AP201 | Mesh panels with over 57,000 holes |
| Builders reusing a long ATX power supply | D31 Mesh | ATX or SFX units up to 220mm long |
| A compact showcase build | 2800X RS-R | A glass side and front with three reverse-rotor fans |
Scroll sideways to see every column.

Key specs side by side
The D33 leads on GPU clearance at 435mm, ahead of the A3-mATX at 415mm. "Not listed" marks GPU clearance where the D31 Mesh leaves the figure out.
| Case | Max GPU length | Max CPU cooler height | Largest radiator | Max PSU length |
|---|---|---|---|---|
| A3-mATX | 415mm | Not listed | 360mm | Not listed |
| D33 | 435mm | 172mm | 360mm | Not listed |
| B4-mATX | 358mm | Not listed | 360mm | 140mm |
| Prime AP201 | 338mm | Not listed | 360mm | 180mm |
| D31 Mesh | Not listed | 168mm | Not listed | 220mm |
| 2800X RS-R | 410mm | Not listed | Not listed | Not listed |
Scroll sideways to see every column.
By price at the time of writing
At our last check the cheapest pick, the B4-mATX, sat in the $50 to $100 tier, 2 tiers in all up to the D33 at $100 to $150; Amazon prices move, so recheck before buying.
| Price tier | Cases |
|---|---|
| About $50 to $100 | B4-mATX, D31 Mesh, 2800X RS-R, A3-mATX, Prime AP201 |
| About $100 to $150 | D33 |

Frequently Asked Questions

Which has the longest GPU clearance: the D33 or the A3-mATX?
The D33 tops GPU clearance at 435mm; the A3-mATX follows at 415mm, 5% apart. The Prime AP201 closes the ranking at 338mm. The D31 Mesh doesn't state a GPU clearance figure, so it sits outside this comparison; 5 of 6 picks are ranked.
How does the Prime AP201 compare with the D31 Mesh on PSU length limit?
Between the top two, it is 220mm on the D31 Mesh against 180mm on the Prime AP201, a 22% difference. The spread runs down to the B4-mATX at 140mm. No PSU length limit figure is published for the A3-mATX, the D33 and the 2800X RS-R, which leaves 3 of 6 picks ranked here.
How does the A3-mATX compare with the B4-mATX on volume?
Between the top two, it is 21.3L on the B4-mATX against 26.3L on the A3-mATX, a 19% difference. The Prime AP201 is at the other end of this group with 33L. No volume figure is published for the D33, the D31 Mesh and the 2800X RS-R, which leaves 3 of 6 picks ranked here.
Is the D33 worth paying more than the B4-mATX?
The spec sheets show GPU clearance (435mm against 358mm) in its favour. The B4-mATX sat in the $50 to $100 tier and the D33 in the $100 to $150 tier when we checked, with 4 other picks between them; pay the difference only if GPU clearance decides your purchase.
What makes the B4-mATX the Smallest Pick?
It carries the badge for a 21.3L volume with two fans included. The A3-mATX is next on volume at 26.3L, so this pick's 21.3L is 19% further out. It makes sense for builders who want the smallest Micro-ATX footprint.
What should I check before buying the 2800X RS-R?
GPU limit in the 2800X RS-R: 410mm, before front fans. In this guide it ranks sixth of 6, as our Best Glass Micro-ATX pick, and third of 5 on GPU clearance (410mm).
Bottom Line
The Lian Li A3-mATX is the best balance of size and support, the JONSBO D33 has the most GPU room, and the Lian Li B4-mATX is the smallest.
The ASUS Prime AP201 is the mesh airflow choice, the JONSBO D31 Mesh suits long ATX power supplies, and the Corsair 2800X RS-R is the compact glass pick.
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About the author
PC Hardware Editor
Alex covers PC hardware, monitors, components, upgrades and peripherals for The PC Journal, with a focus on helping readers understand specifications, compatibility and meaningful product trade-offs.
Covers: Monitors, Graphics cards, Processors, PC components, Peripherals, Upgrades and compatibility
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