CORSAIR RM850x Shift Fully Modular ATX Power Supply - 80 Plus Gold - ATX 3.1 - PCIe 5.1 - Zero RPM - Modular Side Interface - White
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AI Verdict
This 850-watt, 80 Plus Gold, ATX 3.1 power supply features side-mounted modular connections for cleaner cable routing, but demands specific case clearance.
This 850W PSU offers cutting-edge ATX 3.1 and PCIe 5.1 support with a unique side-mounted modular interface for superior cable aesthetics. However, its innovative design makes it a situational fit, as it absolutely requires specific case clearance for the side connectors to be usable, which isn't universal.
If your case lacks the necessary side clearance, look for an ATX 3.1 PSU with traditional rear-facing modular connections.
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Pros
- Modular connections on the side of the PSU allow for direct cable routing behind the motherboard tray, reducing visible clutter.
- Compliant with ATX 3.1 power standard and supports PCIe 5.1, including a 12V-2x6 GPU cable.
- Utilizes 100% 105°C-rated Japanese electrolytic capacitors for unwavering power delivery and longevity.
- The 140mm fluid dynamic bearing fan operates in a Zero RPM mode at low and medium loads, contributing to quiet operation.
- Achieves Cybenetics Platinum efficiency in testing, despite its 80 Plus Gold rating.
- Backed by a ten-year warranty.
Cons
- The side-mounted modular panel requires at least 30mm of clearance on the PSU's left side in the case, limiting compatibility with some PC cases.
- Includes only one 12V-2x6 connector, rated for 300W, which might be a limitation for some higher-powered GPUs like the RTX 4090.
- The flat, ribbon-style cables can be stiff, making precise cable management challenging despite the side connection advantage.
Dimension Scores
The 850-watt unit is 80 Plus Gold certified and frequently performs at Cybenetics Platinum efficiency, exceeding its advertised rating.
The 140mm fluid dynamic bearing fan features a Zero RPM mode, keeping the fan off at loads up to 400W, resulting in near-silent operation for most tasks.
It uses 100% 105°C-rated Japanese electrolytic capacitors and a fluid dynamic bearing fan, backed by a 10-year warranty, indicating high-quality internal components.
The innovative side-mounted modular connections offer a unique advantage for extremely clean cable routing, provided the case has sufficient clearance.
Best For
- New PC builds prioritizing a clean aesthetic with minimal visible cables.
- Systems utilizing ATX 3.1 and PCIe 5.1 graphics cards.
- Cases specifically designed with ample clearance (30mm+) for side-mounted PSU connections.
Not Recommended For
- Compact PC cases or those with limited space between the PSU and the side panel.
- Users with older cases not designed to accommodate side-facing PSU connectors.
- High-end builds requiring multiple 12V-2x6 connectors or a single 600W 12V-2x6 connector.
Watch Out For
- You need to verify your case has at least 30mm of clearance on the PSU's left side, otherwise the side-mounted connectors will be obstructed.
- The included 12V-2x6 GPU cable is rated for 300W, so if you're running a power-hungry GPU like an RTX 4090, you might hit a power limit on that single connector.
- The flat, ribbon-style cables, while aesthetically minimal, are reported by users to be stiff, making tight bends and routing difficult.
Full Specifications
| ASIN | B0CWLWGM67 |
| Brand | Corsair |
| Color | White |
| Series | RMx SHIFT |
| Wattage | 850 watts |
| Model Name | RMx SHIFT |
| Form Factor | ATX |
| Item Weight | 3.75 pounds |
| Manufacturer | Corsair |
| Connector Type | ATX |
| Cooling Method | Fan-based air cooling |
| Output Wattage | 850 Watts |
| Item model number | CP-9020274-NA |
| Compatible Devices | Monitor |
| Product Dimensions | 6.3 x 5.91 x 3.39 inches |
| Item Dimensions LxWxH | 6.3 x 5.91 x 3.39 inches |
| Item dimensions L x W x H | 6.3 x 5.91 x 3.39 inches |
What Buyers Say
The standout feature of this PSU is definitely those side-mounted connectors; users are raving about how much cleaner their builds look because of them, but it's a double-edged sword since you really need to check your case's clearance first. Beyond the cable routing, people are consistently pointing out how quiet it runs, especially with the fan not even spinning at lower loads. The fact that it's ATX 3.1 and PCIe 5.1 ready is a big plus for anyone building a new system with a modern GPU. However, some folks are finding the flat cables a bit stiff to work with, and that single 300W 12V-2x6 connector has been a point of discussion for those with power-hungry cards.
“Man, this thing is a game changer for cable management, my build looks so clean now, but seriously, measure your case first or you're gonna be mad when those side plugs hit the panel.”
Common Praise
- The side-mounted connections make cable management incredibly clean and tidy, with cables disappearing behind the motherboard tray.
- The Zero RPM fan mode means the PSU is completely silent during light to moderate system use.
- It supports ATX 3.1 and PCIe 5.1, making it ready for current and future graphics cards.
- Users report it runs very efficiently, often performing above its 80 Plus Gold rating.
- The build quality, with Japanese capacitors and a 10-year warranty, instills confidence in its longevity.
Common Complaints
- The side connectors won't fit in all cases, specifically those without at least 30mm of clearance on the PSU's left side.
- The flat, ribbon-style cables are stiff and can be difficult to bend and route neatly in tight spaces.
- Some users wish for more than one 12V-2x6 connector, or a higher wattage rating for the single included 300W connector.
- The packaging could be more premium, with some users noting a lack of cable bags or other accessories.
Ownership Tips
- You'll quickly realize if your case has enough room for those side connectors; it's either a perfect fit or a complete no-go.
- The fan really does stay off most of the time, making your PC noticeably quieter during web browsing or light gaming.
- Those flat cables, while looking sleek, are a bit of a wrestle to get into position, especially if you're trying to make tight turns.
- The single 12V-2x6 connector is fine for most GPUs, but if you're pushing a top-tier card, you might find yourself wishing for a higher wattage rating or a second connector.
Frequently Asked Questions
What's the main benefit of the side-mounted connectors?
The side-mounted connectors allow cables to route directly behind the motherboard tray, making for a much cleaner build with fewer visible cables in the main compartment.
Is this power supply truly 80 Plus Gold efficient?
Yes, it is 80 Plus Gold certified, but independent testing shows it often performs at Cybenetics Platinum efficiency levels, meaning it's very efficient.
How quiet is this power supply?
It's very quiet. The 140mm fluid dynamic bearing fan has a Zero RPM mode, so it won't spin at all under low to medium loads, resulting in silent operation.
Does it support the latest graphics cards?
Yes, it's ATX 3.1 compliant and supports PCIe 5.1 with a native 12V-2x6 connector for modern GPUs.
Will this PSU fit in any PC case?
No, the side-mounted connectors require at least 30mm of clearance between the PSU and the side panel of your case for proper cable routing.
Buying Guide
When you're looking at a power supply, you're essentially picking the heart of your PC. It needs to deliver enough power for all your components, especially your graphics card, without breaking a sweat. You also want it to be efficient, so it doesn't waste electricity as heat, and quiet, so it doesn't sound like a jet engine. The modularity of the cables also matters a lot for how clean your PC build will look.
wattage
80 Plus Gold
ATX 3.1 / PCIe 5.1
Fully Modular
Alternatives
If this PSU's side-mounted connectors don't work for your case, look for an ATX 3.1, 850W, 80 Plus Gold fully modular power supply with traditional rear-facing cable connections.
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