psu GPU under powered, suspect bad PSU

[SpaceJellyDonut]

Hi guys,

 

I recently got a new gpu, it's a XFX Radeon RX 580 GTS XXX Edition 8GB card. The card is a great step up from my previous GPU (GTX 750TI) but something's been bothering me, when looking at MSI Afterburner the maximum amount of watts I've seen the card use has been somewhere around 120W and that has only been very briefly. With most demanding games I've played (The Division 2, Devil May Cry 5, Middle Earth: Shadow of War) at maximum of close to maximum details so I know the card should be pushed to its limits. 

 

My problem is I know the RX580 is a 180W TDP GPU, so should it not be using close to that number? I've seen videos of RX570's using in the neighborhood of 150W. 

 

I'm not an expert in how these things work so I might be horribly mistaken about all of this, I mean my RX580 is performing a lot better than my previous card but if it's not using all of its horses then I'm not getting my money's worth. 

 

I suspect it might have something to do with my power supply, I've had it for about 8-9 years I think (I got it out of my mom's old pc I didn't buy it myself), I can't find any information about it online, the only information I have is the details on the power supply itself. I'm linking that information below. 

 

The PSU has 2x6 pin connectors that I'm using for the GPU, my RX580 only has 1x8pin connector but luckily it came with a 2xfemale 6pin to 1xmale 8pin adapter. So both of my PSU's 6 pins are connected to my GPU. 

The thing that I'm worried about is I can't find any information on my PSU on the internet, I don't know if it has any efficiency rating or if it is a good brand? Or that it might be going bad? Maybe one of the 6 pin connectors isn't working? 

My previous GTX750ti ran fine but that was only a 75W card. :/

 

Before I run out and spend money on a PSU I first wanted to find out if I'm mistaken about all of this? 

 

 

Sorry for the long post I just wanted to share as much information as I can to help you.

 

Thanks in advance!

 

[Stormseeker9]

It’s quite a old psu, and probably from a pre built. I would consider buying a new psu. @SpaceJellyDonut

[Gorgon]

This Link shows the 12V rails rated for 384W on that supply and the OEM was Andyson and that it is not 80+ certified.

 

It should be OK as long as you're not rocking a 8770K or 9770K but yes it is almost 10 years old.

 

I'm not familiar with the RX cards but are you overclocking it and have you increased the power limit in afterburner? If not then that might be what's holding you back or you might be CPU limited in which case the card is spending a bunch of time waiting for the CPU and staying cooler as a result.

[r2724r16]

28 minutes ago, Gorgon said:

It should be OK as long as you're not rocking a 8770K or 9770K but yes it is almost 10 years old.

What's an 8770K (and 9770K)?

[Guest]

2 hours ago, SpaceJellyDonut said:

 

 

 

WOW!  That's blast from the past!

 

Vantec is right down the street from me.  I actually go by their office on the way to lunch every day (they're located next to a shopping center with a bunch of restaurants and a movie theater).  I think the only thing they make these days are drive enlcosures.

 

Whether your PSU is to blame for your problems or not, you should replace it.  I mean.. it's SO OLD.  And as pointed out already:  old PSU means old topology.  Double forward, no DC to DC... I mean, just look at the +12V rail.  384W?  And the build quality wasn't great to begin with.  There's a reason we don't see people using these PSUs anymore.  You're lucky it lasted this long.

 

[r2724r16]

11 minutes ago, jonnyGURU said:

I actually go buy their office on the way to lunch every day

You bought their office?

[Guest]

42 minutes ago, r2724r16 said:

You bought their office?

 

[SpaceJellyDonut]

Thanks for all the great replies!

 

@Gorgon I haven't overclocked the GPU no I just left it on default settings, I never saw the CPU (Ryzen 3 2200G) go near 100% usage but I might be mistaken on how all of this works so idk. I'm planning on replacing the CPU with the new Ryzen 3000 series when it comes out so if it is the CPU holding the GPU back I'll know in a few months I guess. I'll try overclocking and increasing the power limit to see if it picks up, I just assumed it would run close to its TDP out of the box. I mean a whole 60W under the rated TDP is a bit much? 

 

@jonnyGURU I thought their name looked familiar, now that you mention it I remember seeing the name and logo when going through the drives section of an online pc parts store here in South Africa I never made the connection for some reason. 

 

Is 384W on the 12V rail not enough for a 180W TDP card? Or does it work differently than I understand? Also when using both the 6pin connectors are they supposed to increase the total amps? I see that each of the 12V rails has 20 amps, so when I use both at the same time is it then the same as 1 x 40amp rail? And both their wattage combined as well? 

 

In any case I think I will replace the PSU afterall I just wanted to make sure I wasn't spending money in the wrong place. I thought maybe the GPU might be broken but seeing as the PSU is more than 8-9 years old it seems like a more likely culprit. And even if it isn't, from what I can gather around the internet it seems like a bad idea to pair computer parts with a dodgy PSU.

 

Thanks again for the help!

[Gorgon]

384W should be fine with a 2200G and an RX580. You should replace the power supply soon though as it is quite old. And if @jonnyGURU is who I think he is then you have an expert opinion there. You’ll definitely need a better supply for your future upgrade.

 

each 6 pin connector is rated at 75W and you can get 75 Watts from the PCIe bus as well so 225W available to the GPU

 

One thing that might be slowing things down is if your graphics card is in the lower PCIex16 slot in an AMD system as these typically run only at PCIe2 (half the speed of PCIe3) and while mechanically x16 are electrically x4 or slower depending on what other peripherals you have installed.

 

Additionally, the 2200G and 2400G have integrated graphics and so only have 8 lanes available for the topmost slot in B450 boards.

[Guest]

8 hours ago, SpaceJellyDonut said:

Is 384W on the 12V rail not enough for a 180W TDP card? Or does it work differently than I understand?

384W would be enough.  What 384W on the +12V of a 520W power supply suggests that it's a very antiquated topology.  Made back in the day before nearly 90%+ of PC's relied on the +12V; which is why most PSUs made today have 90%+ of their power available on the +12V.

 

8 hours ago, SpaceJellyDonut said:

I see that each of the 12V rails has 20 amps, so when I use both at the same time is it then the same as 1 x 40amp rail? And both their wattage combined as well? 

No.  Because 40A x 12V = 480W.  480W > 384W.  What that suggests is you can put a 20A load on one, or the other, but not both.  If there's a 20A load on one, that only leaves 12A for the other until the PSU shuts down or blows up or whatever this PSU tends to do when overloaded.