# ADATA Legend 840 1TB PCIe 4.0 NVMe SSD Specifications (2026)

ADATA Legend 840 1TB uses an Innogrit IG5220 controller with 3D TLC NAND and Host Memory Buffer technology for PCIe Gen4 reads up to 5,000 MB/s and writes of 4,500 MB/s.

Quick answer: The ADATA Legend 840 1TB delivers solid mid-range PCIe 4.0 performance at a budget-friendly price point. The Innogrit IG5220 controller with 3D TLC NAND flash provides 5,000 MB/s reads and 4,500 MB/s writes, which is more than adequate for gaming, general desktop use, and light content creation.

## Specifications

| Specification | Value |
| --- | --- |
| Capacity | 1 TB |
| Interface | M.2 4.0 x 4 |
| Controller | Innogrit IG5220 |
| Memory type | 3D TLC |
| DRAM cache | HMB (no DRAM) |
| Sequential read | 5000 MB/s |
| Sequential write | 4500 MB/s |
| Random read IOPS | 650000 |
| Random write IOPS | 600000 |
| Endurance | 650 TBW |
| MTBF | 1500000 |
| Warranty | 5 years |

## Performance

The 1TB Legend 840 delivers 5,000 MB/s sequential read and 4,500 MB/s write throughput over PCIe 4.0 x4. While these speeds fall short of the 7,400 MB/s ceiling offered by flagship Gen4 drives, they represent a significant improvement over SATA SSDs limited to around 550 MB/s and provide adequate bandwidth for most consumer workloads.

Random 4K performance is where the HMB DRAMless design shows its limitations compared to DRAM-equipped alternatives. Under light desktop and gaming loads the drive feels responsive, booting systems quickly and launching applications without noticeable delay. Under sustained mixed workloads the absence of dedicated DRAM can cause occasional latency spikes as the drive manages the NAND mapping table through the HMB mechanism.

The dynamic SLC cache handles burst write operations well for typical consumer use. During prolonged file transfers exceeding the cache capacity, write speeds drop to the native TLC pace. The 1TB capacity provides a reasonably sized cache pool for most everyday transfer scenarios.

Thermal output from the IG5220 controller is moderate, typically running cooler than flagship Gen4 drives. This makes the Legend 840 a good fit for laptops, Mini-ITX builds, and motherboards without M.2 heatsink coverage. Most users will not need to add aftermarket cooling.

## Endurance, TBW & Warranty

ADATA provides a five-year limited warranty on the Legend 840 series from the date of original purchase. TBW endurance ratings for the Legend 840 scale with capacity, with the 1TB model carrying an endurance rating consistent with other mid-range Gen4 drives in this class. ADATA global support network handles warranty claims through authorized retailers and regional service centers. For warranty service, proof of purchase from an authorized ADATA distributor is required. The five-year warranty term reflects ADATA confidence in the reliability of the Innogrit IG5220 controller platform and the 3D TLC NAND flash under normal consumer operating conditions. Keep your purchase receipt in a safe place, as ADATA requires proof of purchase date to process any warranty claims.

## Pros and Cons

**Pros:**

- 5,000 MB/s reads deliver solid mid-range Gen4 performance
- 3D TLC NAND for better endurance than QLC alternatives
- HMB technology maintains performance without dedicated DRAM
- Moderate thermal output suitable for laptops and compact builds
- Five-year limited warranty from ADATA
**Cons:**

- DRAMless design limits sustained random performance
- Speeds well below the 7,400 MB/s Gen4 flagship ceiling
- SLC cache exhaustion during prolonged large file transfers
- Occasional latency spikes under mixed heavy workloads


## Verdict

The ADATA Legend 840 1TB delivers solid mid-range PCIe 4.0 performance at a budget-friendly price point. The Innogrit IG5220 controller with 3D TLC NAND flash provides 5,000 MB/s reads and 4,500 MB/s writes, which is more than adequate for gaming, general desktop use, and light content creation.

The DRAMless HMB design keeps costs down while maintaining acceptable everyday performance. Thermal requirements are modest, making the Legend 840 versatile across desktop and laptop platforms. If you want Gen4 storage without paying flagship prices, the Legend 840 1TB is a sensible choice from a well-established memory products manufacturer. The drive offers a practical balance of speed, capacity, and affordability for most PC users.

## Frequently Asked Questions

### Does the ADATA Legend 840 1TB have DRAM?

No, the Legend 840 uses Host Memory Buffer (HMB) technology instead of a dedicated DRAM chip. It borrows a small amount of system memory for the NAND mapping table, which keeps costs down.

### What controller does the Legend 840 use?

It uses the Innogrit IG5220 Rainier Pro, a DRAMless PCIe 4.0 x4 NVMe 1.4 controller designed for mid-range Gen4 performance with lower power consumption.

### Is the Legend 840 good for gaming?

Yes, the 5,000 MB/s read speed provides fast game loading times, and the 1TB capacity holds several modern titles. It is a solid gaming storage option at a mid-range price.

### Does the Legend 840 need a heatsink?

The IG5220 controller generates moderate heat and typically does not require a dedicated heatsink. A basic motherboard M.2 cooling solution is sufficient for most use cases.

### Is the Legend 840 compatible with PCIe 5.0 motherboards?

Yes, the drive works in PCIe 5.0 M.2 slots at its native Gen4 speeds of 5,000 MB/s read. It cannot utilize the extra Gen5 bandwidth but functions normally.

### What is the difference between Legend 840 and Legend 800?

The Legend 840 uses the newer Innogrit IG5220 controller with higher speeds (5,000 vs 4,500 MB/s read) and NVMe 1.4 support, while the Legend 800 uses an older controller platform.

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Last updated: 2026-05-23. Source: https://ssdrive.net/adata-legend-840-1-tb