AMD 3700X & RX 5700 XT on a 450W PSU

Zoot

Active member
TL;DR - A 450W PSU is plenty for a 3700X & RX 5700 XT.

My desktop has a 3700X & a Sapphire 5700 XT Pulse which I'm running off a 450W SFX Corsair PSU. Sapphire actually has a 600W PSU requirement up on their website.
https://www.sapphiretech.com/en/consumer/pulse-radeon-rx-5700-xt-8g-gddr6

I did some tests on the power draw from the wall just to see where I'm sitting.

The power measurement shown is from the wall, so you would have to factor in the efficiency aswell. Despite being way under the 600W requirement on Sapphire's website. I'm still nowhere near the limit of what the PSU is rated to supply.

Actually given my numbers a good quality 350W PSU might actually work too. ^_^

Here are the numbers, might be of interest to some - see below:
 

Attachments

  • Stress_Tests_and_Idle_20190906.png
    Stress_Tests_and_Idle_20190906.png
    34.3 KB · Views: 774
  • Games_Power_20190906.png
    Games_Power_20190906.png
    27.2 KB · Views: 753
That should all be good even at peak load, with a 65W TDP(~90W peak draw at stock) processor with a 225W TDP(~260W peak draw) GPU, you wouldn't expect much more than 400W full system load unless with a watercooling setup or something, they do overestimate what's needed on the box for the GPU's PSU recommendations to be safe though as ofc they don't know the whole system (CPU in particular, a 9900K could be +100W's for instance) consumption or quality of the PSU.
 
Last edited:
With the efficiency of the unit, there's about 100 - 150W of room to the max output the PSU is rated for based on my numbers above. So there's even room for some overclocks, probably not balls to the wall stuff on the CPU & GPU at the same time though.

It's interesting that the PSU requirements are so massively overblown. Maybe it's a hangover from the days of crappy PSUs & power hungry components.

Tom did a video measuring the same a number of years back with a 780 Ti on a 450W PSU, he found pretty much the same, I think the 780 Ti used to call for a 600W PSU aswell.

https://www.youtube.com/watch?v=ajiN9aVOv4A
 
Yeah I guess nowadays it might be more common to get people swapping new GPUs into what could be a 7 year old Ivy Bridge system or something still with its 7 year old PSU and overall power consumption requirements, maybe with a mini light show shoved in the case to boot or something lol.
 
Back
Top