GTX 770 with a 430W PSU

[alexfsr]

Hello,

 

I recently got a task to decrypt some files, but i need more gpu horsepower to use with programs like hashcat. I run the it on a server pc i built a little while ago with second hand parts that i got relatively cheap (Asus P6X58d Premium, Xeon X5650@4GHz, 12 GB RAM, 120gb SSD). I also had a 660 lying around and i threw it in, so i needed a power supply. I bought a Seasonic 430W Eco power supply, because i figured it's gonna be enough since i won't really be pushing the server a lot - i use to run servers for games and whatnot. Fast forward to my little task here, the 660 is kind of slow in compute performance. So a friend of mine who has a gtx 770 that he doesn't really use all that much agreed to swap gpus (660 for 770). The problem is, i don't know if the PSU i have is going to be able to power the 770 at 100% load. The cpu will be idling, so the gpu is the only real power consumer. But the psu doesn't have the 2 PCI-e power connectors i need to power the 770, so i'm thinking of using a 2xMolex to 6pin PCI-e adapter, but i don't know if the PSU is going to handle the AMPs. The card wants 42 amps 12v rail, and this power supply has 2 12V rails, 18 amps each, fora  total of 396 watts. The 770 will pull 250W at most (anandtech/tomshardware reviews), but i don't know how the power supply will handle it, if at all.

 

Is it safe to use this power supply with a Molex to Pci-e adapter to power the 770 continuously at full load for couple of days.

[KezzaMcFezza]

2 minutes ago, alexfsr said:

Hello,

 

I recently got a task to decrypt some files, but i need more gpu horsepower to use with programs like hashcat. I run the it on a server pc i built a little while ago with second hand parts that i got relatively cheap (Asus P6X58d Premium, Xeon X5650@4GHz, 12 GB RAM, 120gb SSD). I also had a 660 lying around and i threw it in, so i needed a power supply. I bought a Seasonic 430W Eco power supply, because i figured it's gonna be enough since i won't really be pushing the server a lot - i use to run servers for games and whatnot. Fast forward to my little task here, the 660 is kind of slow in compute performance. So a friend of mine who has a gtx 770 that he doesn't really use all that much agreed to swap gpus (660 for 770). The problem is, i don't know if the PSU i have is going to be able to power the 770 at 100% load. The cpu will be idling, so the gpu is the only real power consumer. But the psu doesn't have the 2 PCI-e power connectors i need to power the 770, so i'm thinking of using a 2xMolex to 6pin PCI-e adapter, but i don't know if the PSU is going to handle the AMPs. The card wants 42 amps 12v rail, and this power supply has 2 12V rails, 18 amps each, fora  total of 396 watts. The 770 will pull 250W at most (anandtech/tomshardware reviews), but i don't know how the power supply will handle it, if at all.

 

Is it safe to use this power supply with a Molex to Pci-e adapter to power the 770 continuously at full load for couple of days.

I used my 650 Ti with molex to PCI-e on a 300W power supply and it even said on websites that that wouldn't be possible but it was. You should be fine but go for a better power supply if you can. Though who am i to talk i'm using a 450W power supply for my i5 4690k and a GTX 970 xD.

 

Hope this helps

[alexfsr]

Just now, ProKeero said:

I used my 650 Ti with molex to PCI-e on a 300W power supply and it even said on websites that that wouldn't be possible but it was. You should be fine but go for a better power supply if you can. Though who am i to talk i'm using a 450W power supply for my i5 4690k and a GTX 970 xD.

 

Hope this helps

If it's not going to burst in flames, it works.

[KezzaMcFezza]

Just now, alexfsr said:

If it's not going to burst in flames, it works.

 yes yes!

[alexfsr]

2 minutes ago, ProKeero said:

 yes yes!

I'm going to try and pray that it stays in one piece. Fingers crossed.

[comicsansms]

A 770 should be fine on a 430W PSU with the right power cables.

 I don't like moles to PCIe adapters, they aren't reliable,  get a good new PSU with the right power connectors, I recommend the EVGA G2, GS or GQ,  anything from Seasonic or XFX. 

[KezzaMcFezza]

Just now, Comic_Sans_MS said:

A 770 should be fine on a 430W PSU with the right power cables.

 I don't like moles to PCIe adapters, they aren't reliable,  get a good new PSU with the right power connectors, I recommend the EVGA G2, GS or GQ,  anything from Seasonic or XFX. 

I ran my 650 Ti of the molex to PCI-e for 1 and a half years with no issues. Maybe i just got lucky?

[Energycore]

1 minute ago, Comic_Sans_MS said:

they aren't reliable

what kinds of risks do you run when connecting a gpu with a molex-pcie? is voltage regulation plain worse?

[alexfsr]

Just now, Comic_Sans_MS said:

A 770 should be fine on a 430W PSU with the right power cables.

 I don't like moles to PCIe adapters, they aren't reliable,  get a good new PSU with the right power connectors, I recommend the EVGA G2, GS or GQ,  anything from Seasonic or XFX. 

I figured that too, but i can't afford to spend money on that right now, sadly.

[don_svetlio]

Considering a 770 uses 200-220W and 120W for the rest of the system - that's around 320-340W. I'd be worried honestly since most 430W PSUs have 380W on the +12V rail

[comicsansms]

10 minutes ago, ProKeero said:

I ran my 650 Ti of the molex to PCI-e for 1 and a half years with no issues. Maybe i just got lucky?

A 650ti doesn’t use much power though. 

9 minutes ago, alexfsr said:

I figured that too, but i can't afford to spend money on that right now, sadly.

When you buy a new PSU,  keep in mind that a good ones have warranties of 10+ years so you can use them for more than 10 years so you don't need to cheap out.

9 minutes ago, Energycore said:

what kinds of risks do you run when connecting a gpu with a molex-pcie? is voltage regulation plain worse?

A fire. 

[Energycore]

Just now, Comic_Sans_MS said:

 

Please elaborate.

[don_svetlio]

1 minute ago, Energycore said:

Please elaborate.

Crap PSU + 100% load = house fire.

[comicsansms]

Just now, Energycore said:

Please elaborate.

Thin wire and most points of failure. 

[Energycore]

12 minutes ago, don_svetlio said:

Crap PSU + 100% load = house fire.

I know that. And also that generally good PSUs have the right number of PCI-E connectors for their rated wattage. But I was wondering about the risks associated with using molex to pci-e adapters, not crappy PSUs.

 

14 minutes ago, Comic_Sans_MS said:

Thin wire and most points of failure.

That makes more sense.

[don_svetlio]

Just now, Energycore said:

I know that. And also that generally good PSUs have the right number of PCI-E connectors for their rated wattage. But I was wondering about the risks associated with using molex to pci-e adapters, not crappy PSUs.

 

That makes more sense.

Molex are rated for 45W - 8-pins for 150W

[Energycore]

1 minute ago, don_svetlio said:

Molex are rated for 45W - 8-pins for 150W

But the molex adapters go 2 molex (90W) to 1 6-pin (75W). Is that wrong?

[don_svetlio]

Just now, Energycore said:

But the molex adapters go 2 molex (90W) to 1 6-pin (75W). Is that wrong?

That is less dangerous but it's still not a great solution. Ran something similar for a year then the PSU started heating up a LOT

[STRMfrmXMN]

A Seasonic S12 430 should be fine TBH