Will an RTX 3080 Run on a 600W PSU with Only 2 PCIe 8-Pin Connectors?

[serein]

Hello! I’ve found a great deal on a second-hand 3080, but my PSU is only 600W and has just 2 8-pin connectors. If we do the math, it looks like the system might barely manage to power everything, but one of the connectors will be unused. So, do you think the system will still boot and run fine? Or am I asking for trouble I’m guessing it might work like an involuntary undervolting situation due to the lack of power… and with my R5 3600, maybe the GPU bottleneck will be a blessing in disguise to help balance things out? Let me know what you think!

Btw GPU is Palit Gamerock.

 

[Scattergrunt]

Not worth it. Upgrade PSU. If everything isnt connected it simply wont boot, if I'm understanding you correctly. If the deal is still good, I'd grab the 3080 anyway, keep it for a bit and then upgrade PSU after to finally use it. 3080 is still a mighty capable card; so its worth the trouble imo. (if the deal is really that good)

 

[Ware]

Nvidia listed a 750 watt PSU for a 10900K system, but noted "A lower power rating may work depending on system configuration"
I would guess that it might "boot and run", and if it's an issue it will show itself under a load.
PSUs may lose some capacity over time, so YMMV.
If you're lucky your PSU will just get hot.
If it's an "involuntary undervolting situation" it wont be a good one.
It's not a blessing to balance things out by reducing performance.

 

[dgianstefani]

The wattage is fine but the amount of connectors isn't. It won't work.

 

[serein]

Well, I know it’s not an ideal choice, but could it work for a short period of time? I’ve thought of it this way: if an 8-pin provides 150W, we’d get 300W from two connectors, and I could think of it as lowering the power limit, essentially underclocking the TDP. Since the CPU would never be enough, maybe it wouldn’t be so bad? After all, performance isn’t directly tied to TDP, right? Also, how bad would the bottleneck be? And considering my motherboard is PCIe 3.0, maybe that could help with the bottleneck a bit. Do you think it would make sense to upgrade to a 5700X or 5600X later, or should I just switch to AM5 completely? Not sure which one makes more sense, but getting a new B550 just for PCIe 4 support would probably be the worst option.

 

[dirtyferret]

it will boot and it will spike past what the PSU can provide once you start gaming
600w are usually more budget orientated platforms compare to 650w units so I would have some caution with the PSU pushed even without the RTX 3080

 

[Marcus L]

You could "in theory" use a splitter though I would recommend upgrading your PSU to one that at least has the 3x8pin connectors

 

[serein]

Not worth it. Upgrade PSU. If everything isnt connected it simply wont boot, if I'm understanding you correctly. If the deal is still good, I'd grab the 3080 anyway, keep it for a bit and then upgrade PSU after to finally use it. 3080 is still a mighty capable card; so its worth the trouble imo. (if the deal is really that good)

I’m not sure about prices around there, but it’s hard to find new ones, and second-hand ones are about $395.

 

[serein]

The wattage is fine but the amount of connectors isn't. It won't work.

I’m considering buying the GP-AP750GM model. What do you think about it? Also, would it be sufficient for a potential CPU upgrade in the future

 

[dirtyferret]

I’m considering buying the GP-AP750GM model

just make sure it's the Aurus AP750GM and not the P750-GM

 

[The Von Matrices]

If you don't want to upgrade your PSU, you can use software like MSI Afterburner to lower the power limit of the GPU. Yes, it will lower the peak performance of the GPU, but it will also make sure it doesn't overload the PSU, and whenever you upgrade your PSU, you can set it back to the default power limit.

 

[Zazigalka]

ampere is notorious for big, momentary power spikes. it'll power on and run, but may often shut down during gameplay (which, for the record, is not something you want to happen). you can also undervolt and underclock, shoot for around 875mv and 1800mhz, see how the card behaves, and if it's fine then keep it like that. limiting fps with rtss would also be highly recommended.

 

[serein]

If you don't want to upgrade your PSU, you can use software like MSI Afterburner to lower the power limit of the GPU. Yes, it will lower the peak performance of the GPU, but it will also make sure it doesn't overload the PSU, and whenever you upgrade your PSU, you can set it back to the default power limit.

If my PSU had 3 PCIe cables, I wouldn’t hesitate at all! By the way, do you have any information about the MAG A750GL model? There's not much price difference between it and Gigabyte, and MSI has a PCIe 5 cable setup which could be useful for me in the future.

 

[Zazigalka]

the internets say it's quite good.

 

[dirtyferret]

MAG A750GL model?

the MSI unit is made by a reputable OEM, the Gigabyte unit is made by an OEM who specializes more in power adapters than PSU
I would personally take the CWT made MSI unit

 

[serein]

Thank you all, have a nice day!