Recently got a motherboard with a pci-e connector on it and it makes me question GPU upgrades

[Factoring]

Hello.

So I recently got an MSI MAG-X870-TOMAHAWK-WIFI and it has a PCI-E connector on it. I'm thinking of upgrading to an 9070 XT, and I see some of them require 3 PCI-E cables plugged into them.

Doing the math, I require 2 cables for the CPU, 1 for the motherboard, and 3 for the video card. That's a total of 6 cables. But after browsing around for a little bit, all power supplies come with max 5 slots! That means I will have to use one cable for two connectors on the video card.

Will doing that hinder performance under max load? My guess is that it could prevent the video card from reaching 340W, but maybe the power delivery from the PCI-E slot saves the day? I really don't know. I don't have a power supply with a 16-pin 12VHPWR connector.

There are also other motherboards that also have a PCI-E connector on them. Do they run into the same issue then?

Thanks.

 

[nomdeplume]

Doing the math, I require 2 cables for the CPU, 1 for the motherboard, and 3 for the video card. That's a total of 6 cables. But after browsing around for a little bit, all power supplies come with max 5 slots! That means I will have to use one cable for two connectors on the video card.

Will doing that hinder performance under max load? My guess is that it could prevent the video card from reaching 340W, but maybe the power delivery from the PCI-E slot saves the day? I really don't know. I don't have a power supply with a 16-pin 12VHPWR connector.

Current PSU: 2x8pin mobo power + 3x8pin GPU.

Believe that extra connector is there for stability but doesn't need to be used. It probably exists to provide security of mind using a 16 pin.

 

[Marcus L]

Hello.

So I recently got an MSI MAG-X870-TOMAHAWK-WIFI and it has a PCI-E connector on it. I'm thinking of upgrading to an 9070 XT, and I see some of them require 3 PCI-E cables plugged into them.

Doing the math, I require 2 cables for the CPU, 1 for the motherboard, and 3 for the video card. That's a total of 6 cables. But after browsing around for a little bit, all power supplies come with max 5 slots! That means I will have to use one cable for two connectors on the video card.

Will doing that hinder performance under max load? My guess is that it could prevent the video card from reaching 340W, but maybe the power delivery from the PCI-E slot saves the day? I really don't know. I don't have a power supply with a 16-pin 12VHPWR connector.

There are also other motherboards that also have a PCI-E connector on them. Do they run into the same issue then?

Thanks.

CPU cables are 8pin and not the same as 6+2 PCIE connectors, neither will either of them interchange unless you force them and want to see some internal fireworks

 

[Factoring]

CPU cables are 8pin and not the same as 6+2 PCIE connectors, neither will either of them interchange unless you force them and want to see some internal fireworks

This is true, but they both go onto the same connectors on the power supplies. This one from ASUS only has 3 of them, for instance (they definitely expect you to be using the new connector instead).

 

[Arkz]

This is true, but they both go onto the same connectors on the power supplies. This one from ASUS only has 3 of them, for instance (they definitely expect you to be using the new connector instead).

View attachment 390479

It has a bunch of accessory connectors next to them that give you 4 pin molex connectors on the end. You could just use one of these

Also depending on your cpu you may only need one 8 pin cpu plug in.

 

[Hereticbar]

Doing the math, I require 2 cables for the CPU, 1 for the motherboard, and 3 for the video card. That's a total of 6 cables. But after browsing around for a little bit, all power supplies come with max 5 slots! That means I will have to use one cable for two connectors on the video card.

That's not true. It depends on the wattage of the power supply. I am pretty sure for most decent power supplies that are over 750w, it is not uncommon to see more than 5 CPU/PCIe 8 pin connectors on them. Although, on some power supplies a couple of the 8-pin connectors might be replaced with a 12VHPWR connector instead.

My Seasonic power supply from 2020, comes with 8 individual CPU/PCIe connectors. I remember wondering why it also came with 2 really nice drawstring bags, then I ended up with bags full of extra unused cables. So, that's what those bags are for.....

 

[eidairaman1]

That's not true. It depends on the wattage of the power supply. I am pretty sure for most decent power supplies that are over 750w, it is not uncommon to see more than 5 CPU/PCIe 8 pin connectors on them. Although, on some power supplies a couple of the 8-pin connectors might be replaced with a 12VHPWR connector instead.

My Seasonic power supply from 2020, comes with 8 individual CPU/PCIe connectors. I remember wondering why it also came with 2 really nice drawstring bags, then I ended up with bags full of extra unused cables. So, that's what those bags are for.....

Same in 2014, its nice to have them though

 

[Hyderz]

My Seasonic power supply from 2020, comes with 8 individual CPU/PCIe connectors. I remember wondering why it also came with 2 really nice drawstring bags, then I ended up with bags full of extra unused cables. So, that's what those bags are for.....

only thing i can think of is that sli was a thing back and the gpus needed those cables...

 

[eidairaman1]

The connector is supplemental, op should try it without using it and i only believe its for heavy overclocking anyway

 

[Fokker]

It depends on the specific PSU, but many come with more than just 3 CPU/PCIE plugs. My 1200W has 8 of them in addition to the 24 pin and 6 SATA/Molex plugs. If you're running a card that has 3 8 pin connectors, I wouldn't be going with the minimum recommended wattage PSU anyway.