# Silicon Power UD90 1TB -- Phison E21T PCIe 4.0 Budget NVMe Review (2026)

The Silicon Power UD90 1 TB is a budget PCIe 4.0 NVMe SSD built on the Phison E21T DRAM-less controller, delivering mid-range Gen4 performance at aggressive pricing.

Quick answer: The 1 TB UD90 is Silicon Power's strongest budget Gen4 offering. Its 4,800/4,200 MB/s speeds are competitive with the WD Blue SN580 1 TB and Kingston NV2 1 TB. The 600 TBW endurance is adequate for any consumer workload. The DRAM-less design means it is not ideal for sustained professional workloads. Choose based on which of the three budget options is cheapest at the time of purchase.

## Specifications

| Specification | Value |
| --- | --- |
| Capacity | 1 TB |
| Interface | M.2 4.0 x 4 |
| Controller | Phison E21T |
| Memory type | Micron TLC |
| DRAM cache | HMB |
| Sequential read | 4800 MB/s |
| Sequential write | 4200 MB/s |
| Random read IOPS | 739000 |
| Random write IOPS | 739000 |
| Endurance | 600 TBW |
| MTBF | 1500000 |
| Warranty | 5 years |

## Performance

The 1 TB UD90 delivers 4,800/4,200 MB/s sequential reads and writes. The HMB architecture provides adequate random I/O for light-to-moderate desktop use. Under sustained writes, the drive transitions to native NAND speeds faster than DRAM-equipped alternatives. Gaming load times are competitive with any PCIe 4.0 drive.

## Endurance, TBW & Warranty

Silicon Power covers the UD90 1 TB with a five-year warranty limited by 600 TBW, equivalent to roughly 328 GB/day over five years. The 2 TB model carries 1,200 TBW.

## Pros and Cons

**Pros:**

- 4,800/4,200 MB/s -- solid budget Gen4 speeds
- Phison E21T -- efficient DRAM-less controller
- 600 TBW endurance with 5-year warranty
- Single-sided PCB -- thin-laptop compatible
- Aggressive pricing
**Cons:**

- No DRAM -- slower sustained random I/O
- Below mid-range Gen4 speeds
- Silicon Power brand less recognized globally


## Verdict

The 1 TB UD90 is Silicon Power's strongest budget Gen4 offering. Its 4,800/4,200 MB/s speeds are competitive with the WD Blue SN580 1 TB and Kingston NV2 1 TB. The 600 TBW endurance is adequate for any consumer workload. The DRAM-less design means it is not ideal for sustained professional workloads. Choose based on which of the three budget options is cheapest at the time of purchase.

## Frequently Asked Questions

### Is the UD90 1TB good for gaming?

Yes — 4,800 MB/s reads provide fast game loading. The 1 TB capacity holds a respectable library. For larger libraries, the 2 TB model is available.

### Does it have DRAM?

No — the UD90 is DRAM-less with HMB (Host Memory Buffer). This keeps costs down but reduces sustained random I/O performance compared to DRAM-equipped drives.

### How does it compare to the Kingston NV2 1TB?

The NV2 rates at 3,500/2,800 MB/s. The UD90 leads on both reads (4,800 vs 3,500) and writes (4,200 vs 2,800). At similar pricing, the UD90 is the stronger performer.

### What is the TBW of the 1TB UD90?

Rated for 600 TBW over five years. The 2 TB carries 1,200 TBW.

### How does it compare to the WD Blue SN580 1TB?

The SN580 rates at 4,150/3,600 MB/s. The UD90 leads on reads (4,800 vs 4,150) and writes (4,200 vs 3,600). Both are DRAM-less. At similar pricing, the UD90 edges ahead.

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Last updated: 2026-05-23. Source: https://ssdrive.net/silicon-power-ud90-1-tb