SP Silicon Power
SP Silicon Power 4TB SSD 3D NAND A55 SLC Cache Performance Boost SATA III 2.5'' 7mm (0.28'') Internal Solid State Drive (SP004TBSS3A55S25)
Bottom line: The SP Silicon Power 4TB SSD 3D NAND A55 SLC Cache Performance Boost SATA ($384.97 on Amazon as of 2026-10-06): 4TB on SATA III, no NVMe slot or M.2 socket required.
As an Amazon Associate, SpecPicks earns from qualifying purchases. Full disclosure →
*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
Pros & Cons
Pros
- ✓ 4TB on SATA III, no NVMe slot or M.2 socket required
- ✓ SLC Cache Technology lifts peak write speeds on bursty transfers
- ✓ 7mm z-height fits Ultrabooks, slim notebooks, and standard 2.5in bays
- ✓ 3-year limited warranty after registering on the SP website
Cons
- ✗ Price, stock, shipping and returns are set by the retailer and may have changed since this page was last updated
Manufacturer description
Built on 3D NAND flash with a controller paired to synchronous NAND, the A55 targets the job most people actually need done: cutting boot times, shortening application launches, and moving large file batches without the stall you get from a mechanical drive. SLC Cache Technology is the piece that matters most here. Incoming data lands in an SLC portion of the NAND first, which lifts peak write performance and reduces write amplification, so endurance improves alongside speed. The 2.5-inch form factor is 7mm (0.28 inch) thick, which is the thin standard that fits Ultrabooks and ultra-slim…
SpecPicks Verdict
SpecPicks scored SP Silicon Power 4TB SSD 3D NAND A55 SLC Cache Performance Boost… using a rating × review-volume × price-fit model applied to published specs and reviews across the ssds & storage category. SP Silicon Power's ssds & storage lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for ssds & storage of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Frequently Asked Questions
Will this fit in my laptop?
It is a 2.5-inch drive at 7mm (0.28 inch) thick, the slim standard used by Ultrabooks and ultra-slim notebooks. If your laptop takes a 2.5-inch SATA drive, a 7mm unit fits; 9.5mm bays fit it too, sometimes with a spacer.
How fast is the Ace A55 compared to a hard drive?
Silicon Power rates it for high transfer speeds via 3D NAND and SLC caching, which shortens boot time and application loading versus a mechanical drive. Exact MB/s figures vary by system and workload; check the product listing for the rated sequential speeds.
What does SLC Cache Technology actually do?
Writes land in an SLC portion of the NAND first, raising peak write performance. It also reduces write amplification, which Silicon Power says improves endurance and extends the drive's lifespan.
What warranty comes with it?
A 3-year limited warranty. Silicon Power asks that you register the drive on the SP official website to receive full manufacturer warranty service and product support.
Is 4TB of SATA worth it over a smaller NVMe drive?
If your machine has a free 2.5-inch bay and you need bulk capacity for game libraries, media, or backups, yes. SATA III caps throughput below NVMe, so keep your OS and latency-sensitive apps on an NVMe drive if you have one.
Key Features
- 3D NAND flash are applied to deliver high transfer speeds
- Remarkable transfer speeds that enable faster bootup and improved overall system performance. The advanced SLC Cache Technology allows performance boost and longer lifespan
- 7mm slim design suitable for Ultrabooks and Ultra-slim notebooks.
- 3-year limited warranty. (Please register your product via SP official website to get the complete manufacturer warranty services, product support and more.)
Full Specifications
| Brand | SP Silicon Power |
|---|---|
| Color | Black |
| Model Name | A55 |
| Read Speed | 500 megabits_per_second |
| Form Factor | 2.5-inch |
| Media Speed | 500 megabits_per_second |
| Model Number | SP004TBSS3A55S25 |
| Built-In Media | 1 x Solid State Drive |
| Hard-Drive Size | 4000 GB |
| Mfr Part Number | SP004TBSS3A55S25AY |
| Number of Items | 1 |
| Special Feature | Shock Resistant |
| Installation Type | SSD |
| Compatible Devices | Laptop |
| Data Transfer Rate | 500 megabytes_per_second |
| Enclosure Material | 3D Nand Flash |
| Additional Features | Shock Resistant |
| Hard Disk Interface | Solid State |
| Customer Package Type | FFP |
| Hard Disk Description | Solid State Drive |
Ready to buy?
SP Silicon Power 4TB SSD 3D NAND A55 SLC Cache Performance Boost SATA III 2.5'' 7mm (0.28'') Internal Solid State Drive (SP004TBSS3A55S25) is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
Related SSDs & Storage
More guides & deep dives from the SpecPicks archive
Browse all articles & guides →- How to Build a Windows 98 Retro PC in 2026
- The Complete Voodoo5 5500 AGP Driver Guide (2026 Edition)
- Best Budget Gaming PC Build 2026 — ~$1,000 ($800 on Sale)
- RTX 4070 Super vs RX 7800 XT — Which to Buy in 2026
- Emulation Hardware in 2026: FPGA, Software, and Cart-Reader Ecosystems
- Best Retro Handhelds in 2026 — From $35 to $500
- Best 1440p Gaming GPUs in 2026
More reviews from the SpecPicks archive
Browse all reviews →- Best Budget Streaming & Content-Creation Gear in 2026: 5 Picks That Punch Above Their Price
- Best 4K Monitor for Reviewing AI-Generated Images on an RTX 3060
- Downsized Your Homelab? Here's What It's Worth
- Best Midrange GPU for 1440p Ultra Gaming in 2026
- Building a 2002 Windows XP Gaming Rig: GeForce 4 Ti, Sound BlasterX G6, CompactFlash Boot
- Intel Arc B580 for Local LLMs in 2026: 12GB for Under $300
- Building a Budget Sim Racing Setup: Logitech G920 vs Thrustmaster TH8A Shifter
- Best Gaming Monitors Under $400 in 2026
- NVIDIA Bankrolls AI Startups to Tighten Its Chip Grip
- Kimi K3 vs Qwen 3.8 for Local Coding Agents in 2026
- Q4_K_M Is Fine for Chat, a Trap for Agents: KV Cache Quant Math for Local Coding
- Step 3.7 Flash Benchmarks: What You Can Actually Run on 12GB
- Plug-and-Play Retro Consoles Compared: Genesis Mini vs SNES vs NES Classic
- Sound Blaster Audigy FX vs G6: Modern PCIe and USB Audio for Retro-Gaming Rigs
- Raspberry Pi 4 8GB vs Pi 5 vs Mini-PC for Local LLMs
- GLM-5.2: Probably the Most Powerful Text-Only Open-Weights LLM
- Best Raspberry Pi Starter Kit for Beginners in 2026
- Does Ryzen 3D V-Cache Speed Up CPU-Only LLM Inference?
- 1998 3dfx Voodoo2 SLI Build Guide: Period-Correct Glide Gaming with a CompactFlash Boot Drive
- How to run Llama 3.1 8B on NVIDIA GeForce RTX 4090
- No Wonder My CPU Was Hitting 100°C: 7 Build Mistakes
- Cactus Hybrid Router: Gemma4-2B Local + Gemini Fallback
- RTX 5090 vs RTX 4090 — is the Blackwell upgrade worth it?
- Best Gaming Headset in 2026 for Gaming and Music
Earliest SpecPicks reviews
Browse full archive →- Best GPU for Llama 3.1 8B (2026)
- Best GPU for Qwen 3 14B (2026)
- Best GPU for Qwen 3 32B (2026)
- Best GPU for Llama 3.1 70B (2026)
- Best GPU for DeepSeek-R1 32B (2026)
- Best GPU for Llama 3.1 405B (2026)
- How to run Llama 3.1 8B on NVIDIA GeForce RTX 5090
- How to run Qwen 3 14B on NVIDIA GeForce RTX 5090
- How to run Qwen 3 32B on NVIDIA GeForce RTX 5090
- How to run Llama 3.1 70B on NVIDIA GeForce RTX 5090
- How to run DeepSeek-R1 32B on NVIDIA GeForce RTX 5090
- How to run Llama 3.1 8B on NVIDIA GeForce RTX 4090