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Max power a pci-e 8 pin can deliver from the psu?

mach

Sorry for the noob question. I've tried to google but sometimes it's hard to find the right words for searching..

I know a 8 pin (6+2) means 150W can be delivered at the gpu side, is it the same story on the psu side too?

To avoid confusion, let's say I need 300W for a graphics card:

 

Assume the psu is fully capable to deliver required power at it's rails.

1. 8 pin (psu) to 8 pin (gpu) + 8 pin (psu) to 8 pin (gpu)  <--two separate cables

2. 8 pin (psu) to 2 x 8 pin (gpu)  <--one splitting cable

 

Which of the above will work? Scenario 1 certainly will as it's how it should be done. But I don't know about scenario 2. 

 

 

 

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i'm not sure about it, but i think it depends on the psu. look at the cables it comes with, those kinds will always work.

so if it has 1x8pin on either side, stick to that, but if it has 8pin on one side and 2x8pin on the other, stick to that.

~i5-7600k @5GHz ~Be Quiet! Dark rock 3 ~MSI GTX 1070 Gaming X 8G ~Gigabyte GA-Z270-gaming K3 ~Corsair Vengeance Red led ~NZXT S340 Elite

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Hello,

It's about basic electrical laws, basically the cables have a section to supports 150W, not 300W. If you send 300W on one of those cables, you are risking to melt it which is fire hazard.

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1 hour ago, Glennieboyyy007 said:

i'm not sure about it, but i think it depends on the psu. look at the cables it comes with, those kinds will always work.

so if it has 1x8pin on either side, stick to that, but if it has 8pin on one side and 2x8pin on the other, stick to that.

I am using the stock cable which has 1x8 pin to 2x8 pin, and I'm suspecting it's not able to provide enough power to my gpu, thus excessive current draw causing sudden reboot. 

1 hour ago, Adimo said:

Hello,

It's about basic electrical laws, basically the cables have a section to supports 150W, not 300W. If you send 300W on one of those cables, you are risking to melt it which is fire hazard.

I understand how these things work. But I don't know how the standard is implemented on power supplies. 

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Oh, I thought you bought some Y splitter to be able to plug your graphic card.

What PSU are you using ? With which configuration ? Might be the total power drawn that can be the issue. I guess that if your PSU came with this type of cable, the connector behind it is made to supplie 300W.

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8 minutes ago, Adimo said:

Oh, I thought you bought some Y splitter to be able to plug your graphic card.

What PSU are you using ? With which configuration ? Might be the total power drawn that can be the issue. I guess that if your PSU came with this type of cable, the connector behind it is made to supplie 300W.

 

It is a silverstone SX600-G. It only has one 8 pin connector for pci-e and comes with a 8 pin to 2x8 pin cable.

A 600W psu should be enough for my 65W i7, vega 64, 1 SSD and a 2.5" hdd. At least I think it is. I'm gonna buy a watt meter tomorrow to find out the power draw.

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If you haven't done any overclocking on both the CPU or GPU, your PSU is enough for powering everything. Apprently your PSU come with a double 6+2 pin connector. So it should be okay.

But you are saying that you are experiencing random reboots, correct ?

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Basically, as per the MOLEX specification, a single 8 pin can handle up to 324W of power. However, the ATX specification takes into account crappy power supplies, hence the lower limit of 150W.

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9 minutes ago, Adimo said:

If you haven't done any overclocking on both the CPU or GPU, your PSU is enough for powering everything. Apprently your PSU come with a double 6+2 pin connector. So it should be okay.

But you are saying that you are experiencing random reboots, correct ?

Yes. Everything is at stock speed.

The system will just suddenly goes off and boot up again during gameplays. 

1 minute ago, TheRandomness said:

Basically, as per the MOLEX specification, a single 8 pin can handle up to 324W of power. However, the ATX specification takes into account crappy power supplies, hence the lower limit of 150W.

Apparently there is an user review of this power supply on newegg claiming that, the system shutting down under load after owning the psu for 6-7 months...Exactly what happened here. Other owners reported psu failures after a few months. I guess this psu is just shit. >:(

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1 minute ago, mach said:

Yes. Everything is at stock speed.

The system will just suddenly goes off and boot up again during gameplays. 

Apparently there is an user review of this power supply on newegg claiming that, the system shutting down under load after owning the psu for 6-7 months...Exactly what happened here. Other owners reported psu failures after a few months. I guess this psu is just shit. >:(

Well, what PSU is it?

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I think he said he had a silverstone SX600-G earlier on the thread. I haven't got any whispers about these being crappy PSUs. But if multiple peoples get the same issues with the same PSU model, it might have something wrong on the internal design

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22 minutes ago, TheRandomness said:

Well, what PSU is it?

It's the Silverstone SX600-G.

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Just now, mach said:

It's the Silverstone SX600-G.

Your i7 can draw around 85W in use and a Vega 64 is capable of drawing up to 400W alone with maxed out power target, so it's starting to cut a little close when it comes to power draw. In theory it'd be fine, so I'd blame drivers for this.

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2 hours ago, TheRandomness said:

Your i7 can draw around 85W in use and a Vega 64 is capable of drawing up to 400W alone with maxed out power target, so it's starting to cut a little close when it comes to power draw. In theory it'd be fine, so I'd blame drivers for this.

I put the card in power saver mode (power limit -25%) and I gamed for 2 hrs no problem!

I think I can deduce that the psu is too weak/worn to power the card?9_9

Less than a year old and I have to shop for a new one, sigh...

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