Thermaltake Tower 300 Black Micro-ATX Case - Vertical Octagonal Design

In this review the Thermaltake Tower 300 is presented for builders who want a distinctive vertical octagonal chassis that still accepts high-end cooling and long GPUs. The bottom line: this Micro-ATX tower is best for enthusiasts who value roomy interior space and flexible water-cooling options, since it supports a 420mm radiator and can fit a 4090-class graphics card while including two 140mm CT fans out of the box. It balances bold looks with practical internal clearance, though buyers should plan for its sizeable footprint.

Key Features

• Octagonal tower chassis: The unique vertical prism shape gives a memorable profile on a desk or shelf while keeping components accessible for builds and maintenance.
• 420mm radiator support: The case accommodates up to a 420mm AIO radiator for serious liquid cooling and lower component temperatures under sustained load.
• Generous GPU and PSU clearance: Supports long graphics cards up to 4090-class length and standard PSUs up to 220mm for flexible component choices.
• Included 140mm fans: Two 140mm CT fans arrive installed to provide immediate airflow and a baseline cooling solution for first-time builders.
• Expandability and accessories: Multiple fan mounting points and the ability to add an optional 3.9' LCD Screen Kit or a Chassis Stand Kit let users personalize cooling and display options.

Who It's For

The Tower 300 is aimed at PC enthusiasts who want a striking, full-featured Micro-ATX case that does not compromise on cooling or component size. It suits water-cooling hobbyists who plan to install a 420mm radiator and builders who need room for a large GPU while keeping a vertical presentation.

It is less suitable for users who need a compact, space-saving ITX solution or who want integrated horizontal mounting without purchasing the optional Chassis Stand Kit. Those seeking the simplest cable management or the smallest desk footprint should consider a slimmer case.

Pros & Cons

Pros

• Well-constructed chassis with ample interior room that reviewers describe as roomy and solidly built.
• Strong water-cooling support with up to a 420mm radiator and multiple fan mounting locations for extensive airflow options.
• Compatibility with very long GPUs and standard 220mm power supplies, reducing constraints on component selection.
• Optional accessories such as an LCD Screen Kit and Chassis Stand Kit allow visual customization and alternate display orientation.

Cons

• Large physical size; some customers compare it to a small refrigerator and it may dominate smaller desks.
• Cable management experiences are mixed, so tidy installation can require extra planning and effort.

Specifications

Case type	Micro Tower (octagonal prism)
Dimensions	551 x 342 x 281 mm (22.5 x 14 x 11.5 in)
Weight	8.3 kg
Included fans	2 x 140mm CT fans
Radiator support	Up to 420mm AIO radiator
PSU clearance	Standard up to 220mm
Optional accessories	3.9' LCD Screen Kit, Chassis Stand Kit (sold separately)

Our Verdict

The Tower 300 is a compelling Micro-ATX case for builders who prioritize cooling capacity and component clearance in a striking octagonal form. It offers good value for enthusiasts who will use its 420mm radiator support and long-GPU compatibility, though the large footprint and mixed cable management feedback mean it is best for users with space and a willingness to plan the build carefully.

Frequently Asked Questions

Can the case fit an RTX 4090-style GPU?
Yes, the Tower 300 is specified to accommodate 4090-class graphics cards and other very long GPUs.

Does the case include fans and what size?
It ships with two 140mm CT fans preinstalled to provide basic airflow out of the box.

Can it be displayed horizontally?
Yes, but horizontal display requires purchasing the optional Chassis Stand Kit separately to secure the case in that orientation.