Seagate FireCuda 520 Review

Introduction

The Seagate FireCuda 520 arrived in late 2019 as one of the first PCIe Gen 4.0 NVMe SSDs to hit the consumer market, targeting enthusiast gamers and high-end PC builders eager to exploit the bandwidth potential of AMD's then-new X570 platform. This M.2 2280 drive positions itself in the flagship tier of internal storage, promising speeds that outpace older PCIe Gen 3 drives by substantial margins. If you're building a gaming rig around a Gen 4-capable motherboard or considering an upgrade from SATA or earlier NVMe technology, the FireCuda 520 represents an interesting piece of SSD history, though its relevance today requires careful consideration given the maturity of the Gen 4 market and the performance improvements made by competing drives in subsequent years.

Product Overview

The FireCuda 520 comes in the standard M.2 2280 form factor with a double-sided design, meaning components populate both sides of the circuit board. It connects via a PCIe 4.0 x4 interface, though it maintains backward compatibility with PCIe 3.0 systems for those who want future-proofing in older platforms. Under the hood, the drive employs the Phison E16 controller, which essentially refines the previous E12 design with Gen 4 support. This controller represents a DRAM-based architecture, and the FireCuda 520 includes dedicated DDR4 cache memory for mapping table storage, which helps maintain consistent performance across varied workloads.

The storage medium consists of Kioxia BiCS4 96-layer TLC NAND flash, which offers a solid balance between performance, endurance, and cost. TLC means each cell stores three bits of data rather than the two bits of MLC or single bit of SLC, providing higher density at the expense of some raw speed and longevity compared to those costlier alternatives. To compensate, Seagate implements a substantial pseudo-SLC cache that treats a portion of the TLC NAND as faster single-level cells during burst write operations. The 1TB model features approximately 370GB of SLC cache, though sustained writes beyond this buffer will see speeds drop to around 600 MB/s as the drive folds data from the cache to native TLC storage.

Capacity options include 500GB, 1TB, and 2TB, with each tier carrying a five-year limited warranty. Notably, Seagate chose not to include a factory heatsink with the FireCuda 520, banking on users having motherboards with integrated M.2 thermal solutions. This design decision keeps the drive slim but places thermal management responsibility squarely on your system configuration.

Performance & Real World Speed

Seagate rates the FireCuda 520 for sequential read speeds of up to 5000 MB/s across all capacities. Write speeds vary by model, with the 500GB version reaching up to 2500 MB/s, the 1TB model hitting up to 4400 MB/s, and the 2TB variant achieving up to 4850 MB/s. Random performance tops out at 760,000 IOPS for reads and 700,000 IOPS for writes on the higher-capacity models, which translates to snappy responsiveness during small file operations like loading game textures or opening applications.

In practical terms, these speeds deliver noticeable improvements over SATA SSDs and older PCIe Gen 3 drives. Game load times see meaningful reductions compared to SATA, shaving several seconds off initial loads in large open-world titles. Windows boot times become nearly instantaneous on a clean installation, though real-world differences between high-end NVMe drives in boot scenarios often prove marginal since operating system loading involves many small file operations rather than purely sequential transfers. Where the FireCuda 520 truly flexes is during large file transfers, such as moving recorded gameplay footage or installing massive game updates. Copying a 50GB file from another fast drive can complete in under a minute under ideal conditions.

The pseudo-SLC cache system means performance characteristics shift depending on workload intensity. Short bursts of writing benefit from the full rated speeds, making the drive feel responsive during typical gaming and productivity tasks. However, sustained write operations like copying your entire game library or rendering large video projects will eventually exhaust the cache buffer, at which point write speeds settle around 600 MB/s on the 1TB model. This behavior is common across consumer drives and rarely impacts gaming scenarios, but content creators working with continuous large file workflows should be aware of this performance floor.

DirectStorage API readiness represents a forward-looking consideration. The FireCuda 520's Gen 4 speeds position it well for this technology, which allows games to load assets directly to the GPU, bypassing CPU decompression. While DirectStorage adoption remains limited as of this writing, the bandwidth headroom ensures the drive won't become a bottleneck as more titles implement the feature.

Thermal Management

PCIe Gen 4 drives generate considerably more heat than their Gen 3 predecessors due to increased controller complexity and data throughput. The Phison E16 controller can become quite toasty under sustained workloads, and without proper cooling, thermal throttling will kick in to protect the drive. When throttling occurs, performance temporarily drops until temperatures decrease, creating inconsistent speeds during heavy use.

Seagate's decision to ship the FireCuda 520 without an integrated heatsink reflects an assumption that buyers will use motherboard-provided thermal solutions. Many modern motherboards, particularly those with PCIe Gen 4 support, include substantial aluminum heatsinks over M.2 slots. These work reasonably well for maintaining acceptable temperatures during typical gaming loads. However, the effectiveness varies widely by motherboard model, and some budget boards offer only thin metal shields that provide minimal cooling benefit.

If your motherboard lacks adequate M.2 cooling or if you're installing the drive in a slot positioned directly under a graphics card where heat can accumulate, aftermarket cooling becomes essential. Third-party heatsinks are relatively inexpensive and can maintain temperatures 10-20 degrees Celsius lower than running bare, preserving sustained performance and potentially extending drive longevity. Installation typically involves cleaning the drive's surface and applying an adhesive thermal pad before attaching the heatsink, a straightforward five-minute task.

For PlayStation 5 users considering the FireCuda 520 for internal expansion, a heatsink is absolutely mandatory. Sony's console requires any aftermarket M.2 drive to include cooling, and the confined internal space makes thermal management critical. The total height including heatsink must remain under 11.25mm to fit within the PS5's M.2 bay, so choosing an appropriately sized cooling solution is essential.

Compatibility

The FireCuda 520 requires a motherboard M.2 slot with key M physical configuration and PCIe 4.0 x4 lane allocation for optimal performance, though it gracefully falls back to Gen 3 speeds in older systems. Most motherboards from the past several years support NVMe boot drives through UEFI firmware, making installation straightforward. Operating system compatibility spans Windows 10 and 11, various Linux distributions, and macOS systems equipped with compatible hardware, though Mac users should verify their specific machine supports third-party NVMe drives before purchase.

For PlayStation 5 internal expansion, the situation requires careful evaluation. Sony specifies that expansion drives must achieve at least 5500 MB/s read speeds and require a heatsink for installation. The FireCuda 520's rated 5000 MB/s read speed falls slightly below Sony's recommended threshold. While some users have reported successful installation and operation, the drive technically doesn't meet official specifications, and you may encounter performance warnings or suboptimal behavior. If PS5 expansion is your primary use case, newer drives specifically marketed as PS5-compatible with read speeds exceeding 5500 MB/s represent safer choices.

Xbox Series X and S compatibility tells a completely different story. Microsoft's consoles require proprietary Seagate Storage Expansion Cards for internal storage expansion, and the FireCuda 520 cannot serve this purpose. You can use it for external storage of Xbox One games via a USB enclosure, but Series X and S optimized titles cannot run from external USB storage regardless of the drive's speed. The proprietary expansion card requirement makes the FireCuda 520 incompatible with Xbox's preferred storage expansion method.

Power requirements remain modest at 3.3 volts, drawing typical power that any modern system can easily supply. The drive supports standard NVMe features including TRIM for maintaining long-term performance and secure erase through the Format NVM command, though it notably lacks hardware-based AES 256-bit encryption found on some competing drives.

Strengths & Weaknesses

The FireCuda 520's most compelling strength lies in its endurance ratings, which stand out even years after release. The 500GB model carries an 850 TBW rating, the 1TB version supports 1800 TBW, and the 2TB option tolerates 3600 TBW, all backed by a five-year warranty. These figures exceed many competing consumer drives and provide excellent peace of mind for users with write-intensive workloads. The Phison E16 controller's fourth-generation LDPC error correction contributes to this longevity, actively managing wear leveling and protecting data integrity.

Performance delivers solid Gen 4 speeds that meaningfully surpass SATA SSDs and earlier NVMe options. The substantial DRAM cache ensures consistent responsiveness across varied workloads, avoiding the stuttering that can plague DRAM-less designs during complex operations. The black PCB and tasteful orange branding create a more premium appearance than generic white sticker drives, though this matters little once installed under a motherboard heatsink.

However, several weaknesses complicate the value proposition. The absence of a factory heatsink creates extra cost and hassle compared to drives that include thermal solutions, particularly frustrating given the FireCuda 520's premium pricing. When it launched, the drive commanded $0.21 to $0.25 per gigabyte, positioning it among the most expensive consumer SSDs despite lacking the included heatsink found on similarly priced competitors. This pricing strategy hasn't aged well as newer Gen 4 drives with comparable or better performance have entered the market at lower prices.

The sequential read speed of 5000 MB/s, impressive in 2019, now sits in the middle of the Gen 4 pack. Competing drives like the Samsung 980 Pro, WD Black SN850X, and Crucial P5 Plus achieve 7000+ MB/s reads, providing tangible benefits in direct comparisons. The FireCuda 520's sustained write performance post-cache, settling around 600 MB/s, also trails newer designs that maintain higher speeds outside their SLC buffers. For content creators working with continuous large file operations, this limitation becomes noticeable.

The lack of hardware encryption represents another omission that may matter to security-conscious users, particularly in business or professional environments where drive-level encryption provides an additional protection layer. While software encryption through Windows BitLocker or third-party solutions works fine, hardware acceleration offers performance and security advantages.

When evaluating the FireCuda 520 against current competition, it occupies an awkward position. It launched as a flagship drive but now competes in a market with faster, often cheaper alternatives. The Samsung 990 Pro delivers better sequential performance and stronger random speeds at similar prices. The WD Black SN850X offers comparable or better speeds with an included heatsink option. The Crucial P5 Plus provides excellent price-to-performance for users who don't need absolute maximum speeds. The FireCuda 520's standout endurance ratings remain attractive, but for most users, newer drives offer better overall value.

Verdict: Should You Buy It?

Buy this if: you already own this drive and want to understand its capabilities, you find it deeply discounted compared to current-generation alternatives and value matters more than cutting-edge speed, you prioritize endurance ratings above all else and need maximum TBW for write-heavy workloads, or you're specifically seeking a PCIe Gen 4 drive for a Gen 3 system where backward compatibility matters and you appreciate the quality Phison E16 controller.

Skip this if: you're building a new gaming PC and want the best current Gen 4 performance for your money as newer drives offer better speeds at similar or lower prices, you need PS5 expansion storage since the drive falls slightly short of Sony's 5500 MB/s recommendation, you're looking for Xbox Series X or S storage expansion because the proprietary expansion card remains your only internal option, you expect a factory heatsink to be included at this price point since competing drives bundle superior cooling solutions, or you're considering Gen 5 drives and your platform supports them as the performance gap justifies the upgrade for specific professional workloads.