Power Supply Another SFF n00b looking for PSU advice.

[CrashDavis]

Hi there - new guy here. I recently started a build, and after getting caught up on the latest I decided on a SFF build and have been lurking here daily soaking it up. This is a great community, and I'm interested in your advice on PSU power levels.

The goals of my build are: powerful but quiet. I've decided on an NCASE M1, which I have in hand. Thinking aircooled only since I don't plan to overclock. Waiting for Ryzen benchmarks/potential GDC announcements before finalizing the processor and GPU, and prepared to take things slow.

In researching PSU needs, I've focused on best noise levels for a given rating. Everything seems to get mixed reviews, but after looking hard at Toms and Jonny, I'm thinking Corsair SF450. The Outervision calculator (below) indicates that 450w should work, but I've noticed a few others - GPU sellers generally - seem to recommend a 500W minimum - even for minis like the new MSI Aero.

Very interested in the experienced people's thoughts. Is the Outervision calculator reliable? Am I over thinking this (move to 650W and call it done....)?

Thanks!

[OuterVision PSU Calculator part list](http://outervision.com/b/km8Np1)

**Motherboard** | Mini-ITX
**CPU** | 1 x Intel Core i7-7700K
**CPU Speed** | 4200MHz
**CPU Vcore** | 1.2V
**CPU Utilization** | 90%
**Memory** | 2 x 16GB DDR4 Module
**Video Card Set 1** | 1 x NVIDIA GeForce GTX 1070
**Core Clock** | 1506MHz
**Memory Clock** | 2002MHz
**Storage** | 2 x M.2 SSD
**Storage** | 2 x PCIe SSD > 500GB
**Other Device** | 2 x USB 3.0 Device
**Other Device** | 1 x LED strip light - 6 LEDs (4.7"/12cm)
**Keyboard** | 1 x Standard Keyboard
**Mouse** | 1 x Standard Mouse
**Fan** | 2 x 92mm
**Fan** | 2 x 120mm
**Computer Utilization** | 8 hours per day
**Load Wattage** | 353W
**Recommended Wattage** | 403W
**Amperage** | +3.3V: 6.0A, +5V: 9.3A, +12V: 28.0A
**Recommended UPS Rating** | 700VA
Generated by OuterVision PSU Calculator 2017-02-25 10:18:07

 

[cmyk78]

Outervision is reliable, and the SF450 will be fine.

 

[confusis]

My opinion - while 450w will do, running a higher wattage PSU will mean you are running down lower in the PSU's wattage range, thus (typically) ending up with a lower fan speed. Obviously don't go for the 800w Silverstone, that's just too far, but a 600w may do you.

 

[CrashDavis]

Thanks for the responses. To confusis point, the Tom's review stated that the Corsair SF600 (which is built similar to the SF450) addressed its higher thermal load with a "more aggressive" fan profile, meaning it came on sooner and spun up higher when compared to the 450. However, depending on my final build and actual usage I may stress the 450 and get identical or worse noise levels. My SFF build will primarily be used for business in the short term, so thinking 450 may be the right compromise.

 

[jeshikat]

There's conflicting info on the fan curve between the SF450 and SF600.

FWIW, 450W is more than enough unless you heavily overclock both the CPU and GPU.

 

[CrashDavis]

Yeah I figgered my mileage will vary on noise. It's good to know that people seem to think that the 450W will carry the planned load. I think I'll go lower power to start and see what happens noise-wise.

I have one other question. Most M1 builds seem to have the PSU fan facing into the case, but with the Corsair SF PSU you get better clearance on the M1 AC connection if you flip the unit around so that the fan is facing "outside" the case. Since the PSU vent faces towards the top no matter what, is there a reason not to do this?

 

[jeshikat]

Like you said, it sometimes helps with the power cable connector to clear the case. Could also be for noise, less fan restriction with it facing inside.

 

[jtd871]

Some of those builds may be trying to take advantage of the PSU as an extra exhaust. Since the SF450 fans are semi-passive, I'd want to ensure that whatever cooling the CPU and GPU need, they get without the PSU and that the PSU can intake fresh air. The proof will be in the pudding, however, so you might want to try different orientations and see what works best.

 

[CrashDavis]

Rightio. Great comments. So - planning to start out with 450W, fan facing external.