Does a 6900XT really need a 900w+ PSU?

mikehhhhhhh · 11 Mar 2021 at 08:46

I've just picked up a Powercolor 6900XT Red Devil and the minimum PSU requirement is 900w!

I don't mind overspeccing, but I can't find a 1000w PSU anywhere. Does it really need that much power with a 300w power limit?

The rest of the system consists of a 5800x, a couple of SSDs and 4 fans, so not exactly heavy!

Stanners · 11 Mar 2021 at 08:49

mikehhhhhhh said:
I've just picked up a Powercolor 6900XT Red Devil and the minimum PSU requirement is 900w!

I don't mind overspeccing, but I can't find a 1000w PSU anywhere. Does it really need that much power with a 300w power limit?

The rest of the system consists of a 5800x, a couple of SSDs and 4 fans, so not exactly heavy!

What PSU do you have and what are your other system components?

mikehhhhhhh · 11 Mar 2021 at 08:53

Stanners said:
What PSU do you have and what are your other system components?

I don't have any PSU currently, this is a new build.

As above, 5800x, 2x SSDs, 4x case fans - oh and a 280mm AIO with 2 fans.

random_matt · 11 Mar 2021 at 09:19

mikehhhhhhh said:
I don't have any PSU currently, this is a new build.

As above, 5800x, 2x SSDs, 4x case fans - oh and a 280mm AIO with 2 fans.

No, do not think so. I went through a PSU calculator the other day involving that card and 5900x. Believe it said 750w.

mikehhhhhhh · 11 Mar 2021 at 09:27

random_matt said:
No, do not think so. I went through a PSU calculator the other day involving that card and 5900x. Believe it said 750w.

My suspicion is that a good quality 850w PSU will be just fine, but I ideally wanted to hear from someone running an overclocked/AIB 6900XT to be sure, instead of taking a gamble.

Dwaindibbly · 11 Mar 2021 at 10:00

Have a scan through the owners thread, I'm pretty sure there are people running decent 850 psu's in there

Dontrocktheboat · 11 Mar 2021 at 10:06

Constant power draw on the 6-series is not bad, but it does get transient power spikes which have been known to trip 1000W power suppliles.

I would stick to the recommendation or "quality" 850W will do.

6900xt is also notorious for coil whine and smaller PSU might exaggerate more coil whine. Pick your PSU carefully I say.

mikehhhhhhh · 11 Mar 2021 at 10:09

If I went 850, I'd proabbly apply a similar budget and go for something like this Asus Platnium PSU

According to Kit Guru it can handle a peak loaf of up to 965w.

Dontrocktheboat · 11 Mar 2021 at 10:10

Nitroo RX 6900XT = Minimum 850 Watt Power Supply
Red Devil 6900XT = Recommended 900 Watt Power Supply
XFX RX 6900XT = Minimum 850 Watt Power Supply.

Dontrocktheboat · 11 Mar 2021 at 10:19

mikehhhhhhh said:
If I went 850, I'd proabbly apply a similar budget and go for something like this Asus Platnium PSU

According to Kit Guru it can handle a peak loaf of up to 965w.

There are better PSU that that. You can get a nice 1000W platinum for 200£

https://www.overclockers.co.uk/be-q...-platinum-modular-power-supply-ca-13y-bq.html

mikehhhhhhh · 11 Mar 2021 at 10:25

Dontrocktheboat said:
There are better PSU that that. You can get a nice 1000W platinum for 200£

https://www.overclockers.co.uk/be-q...-platinum-modular-power-supply-ca-13y-bq.html

Sure, but all out of stock everywhere - hence this thread

Stanners · 11 Mar 2021 at 11:01

Maybe worth asking in the owners thread, I would have thought a good plat 850 would be fine.

ASMB · 11 Mar 2021 at 14:42

Dontrocktheboat said:
Constant power draw on the 6-series is not bad, but it does get transient power spikes which have been known to trip 1000W power suppliles.

I would stick to the recommendation or "quality" 850W will do.

6900xt is also notorious for coil whine and smaller PSU might exaggerate more coil whine. Pick your PSU carefully I say.

As said above its not the average power draw that is the issue, its the power spikes that can trip a psu and cause a shut down. So far the only information I have is that a Corsair psu seems to be a safer bet. I would go with the wattage recommended by AMD to help deal with the power spikes
https://youtu.be/b9ALYCuqtho?t=432

heartburnron · 11 Mar 2021 at 15:25

I have the Red Devil 6900XT. I am running it on an XFX Gold rated 850 PSU and it's absolutely fine. I often run mine with an aggressive overclock, using up to 325W. My benchmarks are competitive too if you have a look at the Firestrike benchmark threads, you'll see me near the top. I'm also using a 125W TDP 5800X chip, high frequency RAM and 6 SSDs. I would say you'll be fine with a gold or platinum 850 PSU if you can't easily get a higher one.

mikehhhhhhh · 11 Mar 2021 at 15:27

heartburnron said:
I have the Red Devil 6900XT. I am running it on an XFX Gold rated 850 PSU and it's absolutely fine. I often run mine with an aggressive overclock, using up to 325W. My benchmarks are competitive too if you have a look at the Firestrike benchmark threads, you'll see me near the top. I'm also using a 125W TDP 5800X chip, high frequency RAM and 6 SSDs. I would say you'll be fine with a gold or platinum 850 PSU.

Thanks - that's just the experience I was looking for.

I took a gamble and ordered the Platinum ROG one I linked above, which did 965w in Kitguru's test.

LoadsaMoney · 11 Mar 2021 at 15:27

No it doesn't, just like the LC Vega 64 didn't need 1000w.

heartburnron · 11 Mar 2021 at 15:31

mikehhhhhhh said:
Thanks - that's just the experience I was looking for.

I took a gamble and ordered the Platinum ROG one I linked above, which did 965w in Kitguru's test.

Damn fine looking PSU that! I really want one but you wouldn't be able to see it in my case.

JohnG7 · 11 Mar 2021 at 15:32

I would take heed of these Transient Spikes as the 3090 is the same, some 850w will work and others give you issues, I repeat again that one member here had an 850w with 2x 1080Ti for years with no issues then crashes on 1x 3090 till he swapped to a 1000w.

mikehhhhhhh · 11 Mar 2021 at 15:32

heartburnron said:
Damn fine looking PSU that! I really want one but you wouldn't be able to see it in my case.

Sadly it'll be hidden away in mine also

mikehhhhhhh · 11 Mar 2021 at 15:33

JohnG7 said:
I would take heed of these Transient Spikes as the 3090 is the same, some 850w will work and others give you issues, I repeat again that one member here had an 850w with 2x 1080Ti for years with no issues then crashes on 1x 3090 till he swapped to a 1000w.

Crashses as in power offs with over current protection, right?