ASUS A21 Black Micro ATX PC Case Supports BTF Hidden Connector Technology, Graphics Cards up to 380mm, 360mm Coolers, & ATX PSUs, Includes Porous Front-Panel mesh and Cable Management Compartment
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AI Verdict
A Micro ATX case supporting 380mm GPUs, 360mm radiators, and BTF motherboards, designed for builders prioritizing component compatibility and cable management.
This case is a strong fit for Micro ATX builders who want to use high-performance components like 380mm GPUs and 360mm liquid coolers. The 33mm cable management space and BTF compatibility simplify building and result in a clean aesthetic.
If you need a smaller footprint, look for Micro ATX cases with maximum GPU lengths under 300mm and limited radiator support.
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Pros
- Accommodates graphics cards up to 380 mm in length, fitting most high-end GPUs.
- Supports up to 360 mm radiators on both front and top panels for extensive liquid cooling.
- Features a 33 mm wide compartment behind the motherboard for effective cable routing.
- Compatible with BTF hidden connector motherboards for a cleaner internal aesthetic.
- Front panel mesh is 40% porous, balancing airflow with dust filtration.
- Reported as easy and stress-free to build in, with clear access to components.
Cons
- Does not include any pre-installed fans, requiring additional purchase for cooling.
- Standard front I/O lacks a USB-C port, which is present on some competing cases.
- Only supports horizontal GPU mounting, limiting display options for some users.
- Its size, while Micro ATX, is noted as being on the larger side for the category, approaching mid-tower dimensions.
Dimension Scores
The 40% porous front-panel mesh and extensive radiator support up to 360mm allow for effective cooling potential.
Since no fans are included, noise levels are entirely dependent on user-selected components, making it an average starting point.
Constructed from steel, plastic, and tempered glass, user feedback indicates a well-executed case that is easy to build in.
The 33 mm wide cable management compartment and BTF compatibility offer superior space and routing options for a Micro ATX case.
Best For
- Builders using BTF hidden connector motherboards for a minimalist look.
- Systems requiring large 360mm AIO liquid coolers for CPU or GPU cooling.
- Configurations with long graphics cards up to 380 mm.
- Users who prioritize ample cable management space for a tidy build.
Not Recommended For
- Compact builds where every millimeter of space is critical, due to its larger Micro ATX footprint.
- Budget-conscious builders expecting included fans, as none are provided.
- Users needing front panel USB-C connectivity without an adapter.
Watch Out For
- The case does not come with any fans, so you'll need to factor in the cost and selection of additional cooling components.
- Despite its Micro ATX designation, some users find its physical dimensions to be closer to a smaller ATX case, potentially impacting desk space.
- GPU mounting is strictly horizontal, which might not suit those wanting to vertically showcase their graphics card.
Full Specifications
| ASIN | B0CPNXZ32P |
| Brand | ASUS |
| Color | A21 ASUS CASE/BLK |
| Series | A21 ASUS CASE/BLK |
| Fan Size | 120 Millimeters |
| Material | Metal |
| Case Type | Tower |
| Model Name | A21 ASUS CASE/BLK |
| Item Weight | 17.6 pounds |
| Manufacturer | ASUSA21 ASUS CASE/BLK |
| Cooling Method | [Inferred: Air or Liquid] |
| Item model number | A21 ASUS CASE/BLK |
| Product Dimensions | 8.66 x 8.66 x 18.31 inches |
| Item Dimensions LxWxH | 8.66 x 8.66 x 18.31 inches |
| Number of USB 2.0 Ports | 2 |
| Number of USB 3.0 Ports | 2 |
| Motherboard Compatability | Micro ATX |
| Power Supply Mounting Type | Bottom Mount |
| Recommended Uses For Product | Gaming |
What Buyers Say
User feedback frequently highlights the case's surprising internal space for a Micro ATX form factor, allowing for large GPUs and extensive liquid cooling solutions. Many appreciate the thoughtful cable management features, including the 33mm routing space and BTF compatibility, which contribute to a clean build process. The 40% porous mesh front panel is consistently praised for its airflow capabilities and ease of cleaning. However, a recurring point is the absence of any included fans, which means an additional purchase is necessary to get started.
“Dude, this case is way bigger than I thought for mATX, but seriously, my 4070Ti fits with room to spare and the cables just disappear behind the motherboard, it was actually easy to build in for once.”
Common Praise
- Accommodates large graphics cards up to 380 mm without issue.
- Provides ample space behind the motherboard for hiding cables.
- Front panel mesh design delivers effective airflow and is easy to maintain.
- Supports 360 mm radiators at both the top and front, offering flexible cooling.
- Building in the case is straightforward and stress-free.
Common Complaints
- No fans are included with the case, requiring separate purchases.
- The standard front I/O lacks a USB-C port.
- Its physical size is larger than some other Micro ATX cases, blurring lines with smaller ATX cases.
- Only allows for horizontal mounting of graphics cards.
Ownership Tips
- The mesh front panel effectively filters dust but requires occasional cleaning to maintain optimal airflow.
- The case's larger size for Micro ATX means it can feel less 'compact' than expected on a desk.
- The lack of included fans means you have full control over your cooling setup, but also an immediate extra cost.
- The 33mm cable management space genuinely makes a difference in keeping the interior tidy, even with a lot of components.
Frequently Asked Questions
Does the ASUS A21 come with any fans?
No, the ASUS A21 does not include any pre-installed fans, so you will need to purchase them separately.
What is the maximum GPU length supported by this case?
The ASUS A21 supports graphics cards up to 380 mm in length.
Can I install a 360mm liquid cooler in the ASUS A21?
Yes, the case supports up to 360 mm radiators on both the front and top panels.
Is there enough space for cable management?
Yes, the A21 provides a 33 mm wide compartment behind the motherboard tray specifically for cable management.
Does this case support BTF hidden connector motherboards?
Yes, the ASUS A21 is compatible with BTF hidden connector motherboards to facilitate cleaner cable routing.
Buying Guide
When picking a PC case, you're essentially choosing the home for all your computer parts. You need to make sure everything fits, especially your graphics card and CPU cooler, and that there's enough airflow to keep things from overheating. Don't forget about cable management; a messy case isn't just ugly, it can block airflow. Also, think about the front ports you'll actually use.
Max GPU Length (380 mm)
Max Radiator Support (360 mm)
Cable Management Compartment (33 mm)
BTF Hidden Connector Technology
Alternatives
If this case doesn't fit, look for Micro ATX cases with smaller physical dimensions, or those that include pre-installed fans for a quicker build.
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