The $170 Seasonic X-750 provides a positive first impression when we unpack it. The 750 W PSU is stowed away in a black velvet case, while the cables come in two nylon packs. Except for Corsair, Seasonic is the only manufacturer in this roundup to use a fully modular cable management system, with even the ATX and CPU cables being modular (though the value of this is questionably, since you're probably not going to use a power supply without hooking it up to your motherboard).
The fan on the Seasonic X-750 only starts running at loads above ~250 W, otherwise staying perfectly silent. The 750 W PSU is 80 PLUS Gold-certified, and its single +12 V rail (preferable to all of the units with dinkier +12 V output spread over multiple rails) can handle up to 62 A.
| Seasonic X-750 | ||||||||
|---|---|---|---|---|---|---|---|---|
| AC Input | 200-240V, 50-60 Hz | |||||||
| DC Output | +3.3 V | +5 V | +12 V (#1) | +12 V (#2) | +12 V (#3) | +12 V (#4) | -12 V | +5 Vsb |
| 25 A | 25 A | 62 A | n/a | n/a | n/a | 1.0 A | 3.0 A | |
| Individual Output | n/a | n/a | ||||||
| Rail Utilization | Sys | Sys | CPU & VGA | |||||
| Combined Output | 125 W | 744 W | ||||||
| Total Continuous Output | 750 W | |||||||
| Peak Output | n/a | |||||||
- New Tests: Ripple And Noise
- Antec TP-750
- Antec TP-750: Results
- be quiet! Straight Power E8
- be quiet! Straight Power E8: Results
- Chieftec BPS-750C
- Chieftec BPS-750C: Results
- Cooler Master GX 750
- Cooler Master GX 750: Results
- Cooler Master Silent Pro Gold 700
- Cooler Master Silent Pro Gold 700: Results
- Corsair CMPSU-AX850
- Corsair CMPSU-AX850: Results
- Cougar SX700
- Cougar SX700: Results
- Enermax Modu 87+ 700 W
- Enermax Modu 87+ 700 W: Results
- NZXT HALE90-750M
- NZXT HALE90-750M: Results
- OCZ Fatal1ty 750 W
- OCZ Fatal1ty 750 W: Results
- Seasonic X-750
- Seasonic X-750: Results
- Sparkle SCC-750AF
- Sparkle SCC-750AF: Results
- Test Configuration, Hold-Up Time, Inrush Current, Peak, And Short Circuit Tests
- Efficiency According To 80 PLUS, Temperature, And Standby Overview
- Efficiency Under Different Load Profiles
- Conclusion And Recommendation





The article doesn't appear to measure noise from during switching and how much noise is introduced to the CPU and bus.
Anyway, it will be a cold day in hell before anyone gets me to switch out my Silverstone 1500 Watt PSU.
You are either lying or very unlucky (got a bad PSU)......I have crossfire 5870s and an i7 965 and all stock cannot exceed 650W at the wall (about 550W actually used) no matter what I try.
I call BS. I could run your setup with my PC power & cooling 750w unit.
http://www.techspot.com/review/289-geforce-gtx-480-sli-versus-radeon-5870-crossfire/page9.html
My next build will be in an NZXT full tower, and I am particularly interested in the Antec 850W, which I believe is the same line as the 750 tested. The report mentioned something about the cables being a bit short for full towers, I'd like to know exact cable lengths, and does anyone know if the 850W model cables may be a little longer?
You're kidding right? You mention the NZXT power supply as "being one of the best", but no mention or recommendation for the Seasonic (even tough according to your own tests the Seasonic handily beats the NZXT)?
Seasonic is one of the, if not thee, best power supply houses in the land. Most of the times if you see a real good power supply from another brand, it turns out it was a Seasonic unit. I'm not saying there are no other good manufacturers out there... But, to not even to get a nod or anything in the conclusion??
Review fail.
So, essentially it will pick away at your RAM. No thanks.
"...its single +12 V rail (preferable to all of the units with dinkier +12 V output spread over multiple rails)..."
I call BS. I'd much rather have multiple +12V rails. With OCP set appropriately, there's no issue of power being "trapped" anywhere, yet it will be safer in the event of near short-circuit conditions.
I'll be building either a SB or BD rig for myself in late Spring or early Summer, and I already picked up the 560W model of the Seasonic "X" line for it ($71 for the one HardwareSecrets reviewed).
Remember too, that 80+ tests at the absurdly low ambient temperature of 23C. While I think their tests are still generally valid, and will certainly clear out the liar-labeled units, for a certified unit to fail by a couple percent under real world conditions is not too unusual.