PSU Advice Needed
PSU Advice Needed
Hello everyone,
I'm setting up a home data storage server and am having trouble deciding which PSU to purchase. The specifications I have are quite detailed, and the old Putervision PSU calculator is no longer available. Here are the details:
- Ryzen 4300G CPU on a full ATX board
- Onboard graphics, no dedicated GPU
- 1 x 128GB NVME SSD
- 8 x 7200RPM 2TB hard disks (SAS)
- 1 PCIe x8 SAS controller
- DVDRW drive
- Multiple fans including 1x120mm, 1x90mm, and 7x80mm (three of these are located in the HDD bays) – all fans are connected via a controller
- 1 Zalman Temperature display and fan controller
- 120mm CPU air cooler
My main concern is that even though I tried a 650W PSU, it seemed to struggle on that power level. The spin-up times for the drives were heavy on both the 12V and 5V rails. Could anyone provide a reasonable estimate for the wattage needed for the maximum 5V rail and total output?
Based on what I found online, hard disks can draw up to 20W each during spinup on either the 12V or 5V rails, though this drops during idle. It’s possible to isolate drive spin-up times if necessary, since my goal is to keep the system running continuously. What I really need is a stable power supply while it's in use.
I suspect the problem lies with the 650W PSU, as I noticed similar issues when testing on a gaming PC with all drives connected to a 750W Corsair unit – the drives ran fine without problems. However, I want to confirm this before replacing the PSU, which has just been returned recently.
Thank you in advance for your help.
It wasn't a strong brand, hard to recall right away and it’s been a few months since I saw it in my purchases. It probably fell into the CIT or another budget line. At first I thought a 650W should be enough, but the real problem was the 9N on the rails—maxing out at under 20A/100W over a 3.3/5V rail. Five drives could handle up to 120W during startup from cold and 100W plus under load. I’m using staggered starts (changing from 1 second to 5 seconds per drive) and considering options between 650W and 850W now, keeping an eye on the 5V/3.3V rail limits in each setup. I’m sure the issue lies in that part of the specs, since I don’t run high loads at 12V.
In the UK, Amazon seems like a solid choice because I’ve got a refund from my last attempt—thumbs up!
Are GameMax PSUs still regarded well these days? I’d steer clear of brands like “Ace Power” and unbranded ones after doing some research lately.
Consider purchasing a reliable PSU. Without a trusted review, check the warranty period. Seven years typically ensures good quality, while ten or twelve years are ideal. Opt for brands like Seasonic or Corsair.
Avoid relying on PSU calculators. They can be very precise when all parameters are known. However, we often lack information about the ageing factor of capacitors or our future needs. Most power usage comes from discrete graphics cards or overclocked CPUs—neither of which you usually use. Hard drives consume minimal power mainly during startup. A 300W unit should suffice. Examine a 750W or 850W model; they are more than adequate. A PSU only draws the power it needs, not the maximum capacity. A robust PSU performs best in the middle of its range and operates more quietly.