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Samsung 990 Pro 4TB — PCIe 4.0 · 7450/6900 MB/s · 4TB
Samsung

Samsung 990 Pro 4TB

PCIe 4.0 · 7450/6900 MB/s · 4TB

86
/ 100
From $360
VS
WD Black SN850X 8TB — PCIe 4.0 · 7300/6600 MB/s · 2TB
Western Digital

WD Black SN850X 8TB

PCIe 4.0 · 7300/6600 MB/s · 2TB

86
/ 100
From $792
Specdex verdict

Dead heat — it comes down to priorities.

In our weighted Specdex score, Samsung 990 Pro 4TB lands at 86 and WD Black SN850X 8TB at 86. With scores tied, the decision hinges on which sub-scores matter most to you.

Pick Samsung 990 Pro 4TB if…

  • ✓M.2 NVMe
  • ✓Competitive per-GB cost
  • ✓TBW scales with capacity

Pick WD Black SN850X 8TB if…

  • ✓M.2 NVMe
  • ✓Competitive per-GB cost
  • ✓TBW scales with capacity
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Winner by scenario

Derived from the sub-score breakdown · not a separate test

Endurance & reliability

Tie

Write endurance and long-term dependability

Effectively tied — neither pulls a 2-point weighted lead.

Value for money

Samsung 990 Pro 4TB

Specdex score per dollar at MSRP

Samsung 990 Pro 4TB more score per dollar ($360 vs $792).

Samsung 990 Pro 4TB 86
vs
86 WD Black SN850X 8TB

Score breakdown

Samsung 990 Pro 4TB
86
read 90
write 88
endurance 88
value 84
WD Black SN850X 8TB
86
read 90
write 88
endurance 88
value 84

Specs side-by-side

Samsung 990 Pro 4TB versus WD Black SN850X 8TB — full spec comparison
Spec Samsung 990 Pro 4TB WD Black SN850X 8TB
Interface
PCIe 4.0
PCIe 4.0
Capacity
4TB
▲ 8TB
Read/Write
7450/6900 MB/s
7300/6600 MB/s

Samsung 990 Pro 4TB

Pros
  • +M.2 NVMe
  • +Competitive per-GB cost
  • +TBW scales with capacity
Cons
  • −Thermals on Gen 5 drives
  • −DRAM-less models slower under sustained load
  • −Require heatsinks in many systems

WD Black SN850X 8TB

Pros
  • +M.2 NVMe
  • +Competitive per-GB cost
  • +TBW scales with capacity
Cons
  • −Thermals on Gen 5 drives
  • −DRAM-less models slower under sustained load
  • −Require heatsinks in many systems

FAQ: Samsung 990 Pro 4TB vs WD Black SN850X 8TB

Which is better, Samsung 990 Pro 4TB or WD Black SN850X 8TB? +

Both score 86 on our weighted rubric — tied. Your best pick depends on the sub-scores above.

Is Samsung 990 Pro 4TB worth the price? +

At $360, Samsung 990 Pro 4TB delivers a Specdex score of 86 — strongest in read.

Is WD Black SN850X 8TB worth the price? +

At $792, WD Black SN850X 8TB delivers a Specdex score of 86 — strongest in read.

Does Samsung 990 Pro 4TB or WD Black SN850X 8TB last longer? +

Based on our long-term update and support ratings, both ship with multi-year support. Battery and reliability scores are visible in the breakdown above.

Which is the better value, Samsung 990 Pro 4TB or WD Black SN850X 8TB? +

Samsung 990 Pro 4TB — more score per dollar ($360 vs $792). Specdex score per dollar at MSRP.