Hands On: InWin P105II 1050W Platinum Power Supply

More recently famed for its stylized cases, InWin has also distributed its own brand of power supplies for as long as any of us care to remember, and always at good value (does anyone remember InWin PowerMan?) Today its PII series helps us continue our search for the perfect, modern replacement power unit for our motherboard test platform.

The P105II includes an AC input cable (US version shown), mounting screws, a bundle of zip ties and enough cables to install up to four graphics cards. It’s sized to the original 150mm depth of legacy PS/2 format, so that it doesn’t require the additional mounting depth of most prior high-capacity units.

Multiple graphics cards aren’t such a big deal for most users, but those who’d like to power them with the P105II will find external input power for up to four cards. Only one of those cards would get the newer 12VHPWR cable, but at least this unit has the capacity to justify a 600W-rated cable (click to expand).

All 1050W of its rated power is available on the 12V rail, though anything you connect to its other rails will borrow from that limit. Its ATX 3.0 rating means that it’s supposed to withstand loads up to 2100W (twice its rated capacity) for at least 100μs and 1260W (120% its rated capacity) for at least 100ms. Certified by cTUVus, TUV, BSMI, RCM, CE, FCC, UKCA and CB to support overcurrent, overvoltage, undervoltage, short circuit, overtemperature and overpower protection, InWin even submitted it to ClearResult to get its efficiency (as well as its power output) independently verified.

The three standard PCIe graphics power cables are the same 24 inches as the main EPS (24-pin ATX) cable, while the 12VHPWR cable is about 4” shorter and the two CPU power (8 pin and 4+4 pin) around 4” longer. There are three triple-drive SATA power cables and a legacy four-wire cable with three four-pin peripheral and one floppy connector (calling the larger of these “Molex” is like calling an Orange Crush “Coke” or a Ford Explorer “Jeep”).

Inside we find a Highpower Active PFC design replete with Japanese caps that include two giant Nichicon 560μF main caps and a slew of Rubycon parts everywhere else. A tiny rocker switch on next to the power cutoff switch allows users to select Zero RPM mode for low loads.

Globe Fan’s S1352512HH uses a Fluid Dynamic Bearing to stay quite even when zero fan mode is disabled.

Looking around at the other options in our lab reveals that this is only the second unit we have to push over 800W at no more than stock mounting depth.

Model	InWin P105II (IW-PS-PII1050W)	Sama P1200 (XPH1200-AP)	XPG Fusion 1600 Titanium	Corsair AX860i	be quiet! Dark Power Pro 850
+12V Max (Amps)	87.5A	100A	133.3A	71.6A	70A
12VHPWR	1	2	2	0	0
6+2 Pin PCIe	3	3	6	4	4
EPS12V	2	2	2	2	2
80Plus Cert.	Platinum	Platinum	Titanium	Platinum	Platinum
Weight	1.70kg	1.75kg	2.59kg	1.90kg	2.26kg
Depth	150mm	150mm	210mm	160mm	194mm
Warranty	10-years	10-years	12-years	10-years	10-years

Having noted its quality construction and array of certifications, our test merely compares the P105II’s power consumption to other contenders at our test platform’s full (~735W combined) load.

System Configuration
CPU	Intel Core i9-13900K: 24C/32T, 3.0-5.8 GHz, 36 MB L3 Cache, LGA 1700, Locked at 5.0P/4.0E GHz, 1.25V Core
CPU Cooler	Alphacool Core 1 LT Aurora, Eisbecher D5 150mm, NexXxoS UT60 X-Flow 240mm
Motherboard	ASRock Z790 Taichi Carrara, BIOS 12.13 (04/23/2024)
RAM	Crucial Pro OC Gaming Edition DDR5-6400 32GB Kit
Graphics	ASRock RX 7700 XT Phantom Gaming 12GB OC 2276 MHz GPU, 2599 MHz Boost, GDDR6-18000
System Drive	Crucial T700 PCIe Gen5 2TB M.2 SSD
Test Condition
CPU Load	Prime95 v30.8 build 16 Torture Test, Small FFTs
GPU Load	Furmark 2.7.0.0 GL Test, 1920×1080

P105II Basic Power Test Result

Remembering that we have but one test condition by which to compare the suitability of each unit to replace the Dark Power Pro 850W that currently resides in our test system, we see that the P105II takes third place behind the other two new models.

Though a perfectly useful unit, we find no compelling reason to select the P105II over Sama’s P1200. Not only does the competing product have a slightly higher power rating, it’s also been validated by a slightly more stringent tester: Cybenetics. With the competition this tight, we can’t fathom why any manufacturer would want to skip that last cert.