Seasonic
Seasonic Vertex PX-1200
1200 W · 80+ Platinum · ATX 3.0
93
/ 100
From $289
VS
Seasonic Vertex PX-1200 wins by 3
Corsair
Corsair RM850x Shift
850 W · Gold
90
/ 100
From $179
Specdex verdict
Seasonic Vertex PX-1200 takes it — here’s why.
In our weighted Specdex score, Seasonic Vertex PX-1200 lands at 93 and Corsair RM850x Shift at 90. That puts Seasonic Vertex PX-1200 ahead by 3 points — a narrow margin driven mostly by its strengths in the categories below.
Pick Seasonic Vertex PX-1200 if…
- ✓Rock-solid ripple
- ✓Platinum efficiency
- ✓Long 12-year warranty
Pick Corsair RM850x Shift if…
- ✓Modular cabling on most
- ✓ATX 3.1 / 12V-2x6 support
- ✓10-year warranty on many
Seasonic Vertex PX-1200 93
vs 90 Corsair RM850x Shift
Score breakdown
Seasonic Vertex PX-1200
93 efficiency 96
noise 92
cables 90
value 86
Corsair RM850x Shift
90 efficiency 90
noise 86
cables 86
value 84
Specs side-by-side
| Spec | Seasonic Vertex PX-1200 | Corsair RM850x Shift |
|---|---|---|
| Wattage | 1200 W | 850 W |
| Efficiency | 80+ Platinum | Gold |
| Standard | ATX 3.0 | — |
| Connectors | 1× 16-pin 12VHPWR (600W) | — |
Seasonic Vertex PX-1200
Pros
- +Rock-solid ripple
- +Platinum efficiency
- +Long 12-year warranty
Cons
- −Heavy at 2.6 kg
- −Expensive
- −Cables stiff
Corsair RM850x Shift
Pros
- +Modular cabling on most
- +ATX 3.1 / 12V-2x6 support
- +10-year warranty on many
Cons
- −Bulky on higher wattages
- −Fan noise varies by load
- −Cable length may not fit some cases
FAQ: Seasonic Vertex PX-1200 vs Corsair RM850x Shift
Which is better, Seasonic Vertex PX-1200 or Corsair RM850x Shift? +
Seasonic Vertex PX-1200 scores 93 on our weighted rubric — ahead by 3. Your best pick depends on the sub-scores above.
Is Seasonic Vertex PX-1200 worth the price? +
At $289, Seasonic Vertex PX-1200 delivers a Specdex score of 93 — strongest in efficiency.
Is Corsair RM850x Shift worth the price? +
At $179, Corsair RM850x Shift delivers a Specdex score of 90 — strongest in efficiency.
Does Seasonic Vertex PX-1200 or Corsair RM850x Shift 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.