Top Posts

how to install sli graphics cards how to cancel newegg order power supply connectors on motherboard difference between 4gb and 8gb msi afterburner 64 bit games paper clip trick power supply is bitcoin mining worth it six pin to eight pin adapter molex to 6 pin adapter how to convert bitcoins to cash msi afterburner fan speed locked 6 pin to 4 pin molex convert sata power to molex pci express 3.0 x16 riser esop employee stock option plan asus republic of gamers forum how to overclock with msi afterburner build a bitcoin mining rig 500w power supply best buy amd display driver stopped responding how to write commands in ubuntu which pcie slot for graphics card asus m5a97 graphics card compatibility windows has stopped this device code 43 sapphire tri x r9 290x oc display driver stoped responding and has recovered how much bandwidth does bitcoin mining use the promise of prediction markets motherboards with pci express 3.0 bitcoin mining return on investment msi bios boot from usb how to install exe in ubuntu dalhousie university halifax ns canada

Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Noob question: Possible to use 1000 Watt & 750 Watt PSU together?

SaakjeSaakje Member Posts: 21
Hi Guys,

I am building my second mining rig and I want to do a quick sanity check before blowing up the building.
Is it safe to use a 1000 Watt psu & 750 Watt PSU of different brands together on one rig?
I had some power issues with my first mining rig so I was thinking of adding the extra muscle.

I want to use the Corsair RM750 (Gold) with the PSU Be Quiet! Power Zone 1000W 80 Plus Bronze.

Any tips on this?

Thanks in forward!

Comments

  • theneogeo1982theneogeo1982 Member Posts: 530 ✭✭✭
    Yes, get add2psu
  • SaakjeSaakje Member Posts: 21

    Yes, get add2psu

    Ok thanks! What is the benefit over add2psu against using a paperclip to connect green and black?
  • SaakjeSaakje Member Posts: 21
    nuhanenu said:
    Ok thanks! I did not knew of the existence of these cabels. What is the benefit of double powering the motherboard? Before I just used a paperclip to connect the black and green cabels. Does it work smarter for instance if it is connected to the motherboard?
  • theneogeo1982theneogeo1982 Member Posts: 530 ✭✭✭
    Saakje said:

    Yes, get add2psu

    Ok thanks! What is the benefit over add2psu against using a paperclip to connect green and black?
    Safer and will work in unison with main PSU
  • otoxotox Member Posts: 41
    The benefit is they turn on in unison, the hack method can have a tendency to power on things at different times potentially causing permanent damage to certain components.
  • SaakjeSaakje Member Posts: 21
    otox said:

    The benefit is they turn on in unison, the hack method can have a tendency to power on things at different times potentially causing permanent damage to certain components.

    Ok, awesome! Can you also get more juice out of the 2 PSU's if you combine them using add2psu?
    For instance, now I have a setup with 2 x 750W Corsair G750M powering 5x 7970's I have a 6th 7970 GPU but adding this one makes the system fail due to not enough power. Might adding this add2psu unit potentially solve this problem?

  • otoxotox Member Posts: 41
    Yes, PSUs are most efficient below 50% load. But the difference IMO is probably negligible, ive never measured it so I wouldn't know for fact.
  • newmznewmz AustraliaMember Posts: 299 ✭✭✭
    I just use the "paperclip" method, and I always turn on the paperclip PSU first. It works fine.
    All that the add2psu does is detect +12v from the primary PSU and use a relay to make the paperclip connection for you. It doesn't do anything to spread power load more effectively, or make a "safe" electrical connection between the PSUs. It's just a switch.

    Something you have to know about dual PSU rigs is that with the 2nd PSU - the paperclipped one, you must ONLY use it for the graphics card 6/8 pin +12v power. Use the first PSU (the one that powers the motherboard, CPU, RAM, SSD and first 2 or 3 graphics cards) for the power to ALL the risers. NEVER use the 2nd PSU for riser power, just the graphics card power.
  • SaakjeSaakje Member Posts: 21
    newmz said:

    I just use the "paperclip" method, and I always turn on the paperclip PSU first. It works fine.
    All that the add2psu does is detect +12v from the primary PSU and use a relay to make the paperclip connection for you. It doesn't do anything to spread power load more effectively, or make a "safe" electrical connection between the PSUs. It's just a switch.

    Something you have to know about dual PSU rigs is that with the 2nd PSU - the paperclipped one, you must ONLY use it for the graphics card 6/8 pin +12v power. Use the first PSU (the one that powers the motherboard, CPU, RAM, SSD and first 2 or 3 graphics cards) for the power to ALL the risers. NEVER use the 2nd PSU for riser power, just the graphics card power.

    Thanks!
    I actually am using the second PSU for powering 3 GPU's and the powered risers that are connected to these GPU's. I was in the understanding that the PSU that powers a GPU must also power the powered risers that are connected to this GPU. Is this not the case?
  • newmznewmz AustraliaMember Posts: 299 ✭✭✭
    No not the case. 1st PSU which is the system PSU (mobo, CPU, 1st graphics cards, etc) should power everything, except 2nd PSU does the 6/8 pin +12v power to the extra graphics cards it is for. If you use the 2nd PSU for riser power it may "fight" with the 1st PSU when trying to set stable +12v output.
  • SaakjeSaakje Member Posts: 21
    newmz said:

    No not the case. 1st PSU which is the system PSU (mobo, CPU, 1st graphics cards, etc) should power everything, except 2nd PSU does the 6/8 pin +12v power to the extra graphics cards it is for. If you use the 2nd PSU for riser power it may "fight" with the 1st PSU when trying to set stable +12v output.

    Ok thanks,
    To be honest I find this very confusing. But I did change it now, so now my 1st PSU powers ALL powered risers, the mobo, CPU and GPU 1 & 2. And the 2nd PSU powers GPU 3,4,5.
  • boysieboysie Member Posts: 590 ✭✭✭
    newmz said:

    No not the case. 1st PSU which is the system PSU (mobo, CPU, 1st graphics cards, etc) should power everything, except 2nd PSU does the 6/8 pin +12v power to the extra graphics cards it is for. If you use the 2nd PSU for riser power it may "fight" with the 1st PSU when trying to set stable +12v output.

    bollox.

    that's not true...you can do either way but normally its best to isolate cards power to 1 psu, many threads on this and apparently there is a requirement that power from the 6/8 can be from a different source and must not cause grounding loops...but a requirements and actual implementation isolating this might not always be optimal. hell AMD didn't even follow the power rating from the pci-e and apparently the pci-e was meant to purly power the mem, but now it seems it draws from both so having this from different psu seems silly.

    If you have miss matched sizes I can see why you might want more power to come from 1 psu and that may work for you but I would just use things in a simple way and 1 psu for both 6/8 pin and riser...its very basic and very simple...it also allows for lots more strings to be used and no need to double up on the molox/sata strings which can overload the 12v strings and melt them and this is easily avoidable using my method

    Boysie
  • SWDude26SWDude26 Member Posts: 132 ✭✭
    I setup my rig last night with the 2nd PSU power both the 6/8 Pins and the riser for the 3rd card.

    Stable so far.
  • SaakjeSaakje Member Posts: 21
    edited August 2016
    Yes I guess both ways are possible. I had my setup running GPU 3,4 & 5 both Risers and 6/8 pins on the second PSU non stop for a few weeks.
    Thing is, you don't want a ticking time bomb right...
or to comment.