Skip to main content
Seasonic PRIME PX-1600 1600W Power Supply ATX 3.1 & PCIe 5.1 Ready | 80 Plus Platinum & Cybenetics Titanium Fully Modular Dual 12V-2x6 RTX 5090 AMD RX 9000 Ready AI Workstation 12 Yrs Warranty
Seasonic

Seasonic PRIME PX-1600 1600W Power Supply ATX 3.1 & PCIe 5.1 Ready

Bottom line: The Seasonic PRIME PX-1600 1600W Power Supply ATX 3.1 & PCIe 5.1 Ready ($496.92 on Amazon as of 2026-10-21 12:20 UTC): 1600W headroom runs an RTX 5090 or RX 9000 build with room for a second GPU; main trade-off: 499.99 USD is a steep buy-in if you are not running dual GPUs. Another in-stock pick with the same 1600W 80 Plus Platinum fully modular ATX power supply: the Seasonic PRIME TX-1600 Noctua Edition, $754.00 on Amazon as of (price may vary).

$496.92

As an Amazon Associate, SpecPicks earns from qualifying purchases. Full disclosure →

Buy on Amazon — $496.92 Also on eBay → Compare to similar power supplies

By , Founder & Editor-in-Chief · Listing data updated

Mike Perry — Hardware researcher since 2014, focused on GPU performance across gaming, rendering, and local-LLM inference. Synthesises community benchmarks, manufacturer specs, and public forum data into actionable buying guides.

*Price sourced from Amazon.com. Last updated 2026-10-21. Price and availability subject to change.

Pros & Cons

Pros

  • ✓ 1600W headroom runs an RTX 5090 or RX 9000 build with room for a second GPU
  • ✓ Dual native 12V-2x6 cables feed two high-draw cards without daisy-chained adapters
  • ✓ ATX 3.1 / PCIe 5.1 spec handles modern GPU transient power spikes
  • ✓ Cybenetics Titanium plus 80 PLUS Platinum puts it above typical Gold-rated units
  • ✓ 12-year warranty and 100% Japanese capacitors back long AI-workstation duty cycles

Cons

  • ✗ 499.99 USD is a steep buy-in if you are not running dual GPUs
  • ✗ 1600W is well past what a single mid-range GPU build will ever draw
  • ✗ Hybrid fan mode means the 135 mm fan does spin up under sustained heavy load
  • ✗ Physical size and stiff modular cabling can be tight in compact ATX cases

Related Products

Other products in this category you may like:

SpecPicks Verdict

SpecPicks scored Seasonic PRIME PX-1600 1600W Power Supply ATX 3.1 & PCIe 5.1 Ready using a rating × review-volume × price-fit model applied to our editorial and benchmark analysis across the power supplies category. Seasonic's power supplies 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 power supplies 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.

Key Features

  • ATX 3.1 / PCIE 5.1 ready. Dual native 12V-2x6 connectors
  • 80 PLUS Platinum and Cybenetics Titanium certified
  • Ideal for AI workstations
  • 100% Japanese capacitors
  • Hybrid fan control with 135 mm FDB fan

Full Specifications

BrandSeasonic
Wattage1600 watts
Fan Size13.5 centimeters
Model NamePrime PX-1600 ATX 3.1
Unit Count1 Count
Form FactorATX
Model NumberPrime PX-1600 ATX 3.1
Connector TypeATX
Cooling MethodAir
Number of Fans1
Output Wattage1600
Item Dimensions8.3 x 6 x 3.4 inches
Mfr Part NumberPrime PX-1600 ATX 3.1
Number of Items1
Compatible DevicesComputer
Power Supply DesignFull Modular
Warranty Description12 Years
Maximum Input Voltage230 volts
Minimum Input Voltage90 volts_of_alternating_current
Item dimensions L x W x H8.3 x 6 x 3.4 inches
Full listing titleSeasonic PRIME PX-1600 1600W Power Supply ATX 3.1 & PCIe 5.1 Ready | 80 Plus Platinum & Cybenetics Titanium Fully Modular Dual 12V-2x6 RTX 5090 AMD RX 9000 Ready AI Workstation 12 Yrs Warranty

Performance Data

View gaming FPS, AI inference throughput, and synthetic scores for the NVIDIA GeForce RTX 5090 — the core hardware component in this product. Benchmarks sourced from TechPowerUp, PassMark, and the r/LocalLLaMA community.

Which local LLMs fit in 32 GB?

32 GB holds a 30–35B model at Q4 with a long context window; a 70B model runs only with layers resident in system RAM.

  • ✅ 7–9B models (Llama 3.1 8B, Qwen 3 8B) — fits at Q4
  • ✅ 12–14B models (Qwen 3 14B, Phi-4) — fits at Q4
  • ✅ 20–27B models (Gemma 3 27B, Mistral Small) — fits at Q4
  • ✅ 30–35B models (Qwen 3 32B, QwQ 32B) — fits at Q4
  • ❌ 70B models (Llama 3.3 70B, Qwen 2.5 72B) — needs 48 GB+

Across 6 community runs from 4 sources, the NVIDIA GeForce RTX 5090 generates a median 185.9 tok/s on 7–9B models at Q4 (per Hardware Corner).

Per-model VRAM guide: which GPU for which LLM →

Ready to buy?

Seasonic PRIME PX-1600 1600W Power Supply ATX 3.1 & PCIe 5.1 Ready | 80 Plus Platinum & Cybenetics Titanium Fully Modular Dual 12V-2x6 RTX 5090 AMD RX 9000 Ready AI Workstation 12 Yrs Warranty 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.

Buy on Amazon — $496.92

*Price sourced from Amazon.com. Last updated 2026-10-21. Price and availability subject to change.

Related Power Supplies

Keep exploring SpecPicks

Other buying guides

Browse the catalog

Editorial

More guides & deep dives from the SpecPicks archive

Browse all articles & guides →

More reviews from the SpecPicks archive

Browse all reviews →

Earliest SpecPicks reviews

Browse full archive →
Seasonic PRIME PX-1600 1600W Power Supply ATX 3.1 & PCIe 5.1 Ready | 80 Plus Platinum & Cybenetics Titanium Fully Modular Dual 12V-2x6 RTX 5090 AMD RX 9000 Ready AI Workstation 12 Yrs Warranty
$496.92
View on Amazon →