Topic: Dummy Plugs/ Multiple GPUs (Read 30505 times)
Well if I did I wouldn't post now right?
You didn't notice this was a 2 year old thread, right?
Here's what I did
I have 2 7970 and a onboard video card.
At first I was using one of my 7970 HDMI to mine/browse on my computer, but I did notice it effect my harsh rate a bit (jumpy at 620kh/s - 580kh/s ish when I load stuff). So I was thinking maybe I should use my onboard video card to display instead, but when I switch the hdmi cable to my onboard, system wasn't detecting the 2 7970.
So I found a way to mine with my 2 7970 without effecting my harshrate and continue to browse on the internet with stable harshrate and without using a dummy plugs either.
1 HDMI from onboard to monitor, 1 DVI to vga from 1 7970 to the same monitor.
Set onboard screen as main, and 7970 as extend. Done (You can't just use 1 montior or it won't detect the 7970.)
Harshrate is stable at 620kh/s even when I load 5 tabs on chrome.
I am not sure if my 7970 will harsh even higher if it didn't have to render the extended screen. Might switch the DVI cable to my other 7970 to find that out.
Update: (It does not effect the harshrate unless you have something on that screen.)
I have 2 7970 and a onboard video card.
At first I was using one of my 7970 HDMI to mine/browse on my computer, but I did notice it effect my harsh rate a bit (jumpy at 620kh/s - 580kh/s ish when I load stuff). So I was thinking maybe I should use my onboard video card to display instead, but when I switch the hdmi cable to my onboard, system wasn't detecting the 2 7970.
So I found a way to mine with my 2 7970 without effecting my harshrate and continue to browse on the internet with stable harshrate and without using a dummy plugs either.
1 HDMI from onboard to monitor, 1 DVI to vga from 1 7970 to the same monitor.
Set onboard screen as main, and 7970 as extend. Done (You can't just use 1 montior or it won't detect the 7970.)
Harshrate is stable at 620kh/s even when I load 5 tabs on chrome.
I am not sure if my 7970 will harsh even higher if it didn't have to render the extended screen. Might switch the DVI cable to my other 7970 to find that out.
Update: (It does not effect the harshrate unless you have something on that screen.)
I'm running WinXP x64 and 2x 6970's
I have tried dummy plugs, but can't get the second card to go active.
This is what I tried:
http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html
Even tried this:
http://blog.zorinaq.com/?e=11
No luck on either, any ideas on what else I can try?
EDIT:
Figured it out, you have to extend your desktop on the other card.
I have tried dummy plugs, but can't get the second card to go active.
This is what I tried:
http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html
Even tried this:
http://blog.zorinaq.com/?e=11
No luck on either, any ideas on what else I can try?
EDIT:
Figured it out, you have to extend your desktop on the other card.
--delete please--
how did you measure the 1%?
I guess I should have just stated the overall hash rate increase,
350 -> 356
300 -> 304
obviously the increase is because the gpu no longer has to render the desktop
Measurement: 3 5850 cards. Two miners on each card summed up. Two measurements before removal of plugs, two measurements after. Phoenix with flag -a 128 for measurement averaging. Waiting time between measurements ~2 min.
I am quite reliefed that with this result I do not have to look for a way to make the cards work without dummy plugs on win xp.
how did you measure the 1%?
I guess I should have just stated the overall hash rate increase,
350 -> 356
300 -> 304
obviously the increase is because the gpu no longer has to render the desktop
OK, I would like to sum up what we know about dummy plugs. It has been bothering me quite a bit. Please correct and extend.
- Linux: no dummy plugs needed
- Win7: it is possible to force activate screens in display properties or change the EnableULPS registry entry
- WinVista: ?
- WinXP: dummy plugs or crossfire needed? did anyone manage to get it to work some other way?
That's 100% false and not working. ULPS is the powersaving feature on cards that are already in CrossfireX therefor active.
I'm really surprised nobody has mentioned the benefit to NOT using dummy plugs.
I use the swap-monitor trick to get them all going because, for example, my 5830 does 300 MH/s with the monitor plugged in. When I unplug the monitor to swap over to the 5850, the hashrate goes up to 304 MH/s.
I'm assuming dummy plugs would decrease all hashrates by 1%
I use the swap-monitor trick to get them all going because, for example, my 5830 does 300 MH/s with the monitor plugged in. When I unplug the monitor to swap over to the 5850, the hashrate goes up to 304 MH/s.
I'm assuming dummy plugs would decrease all hashrates by 1%
how did you measure the 1%?
I'm really surprised nobody has mentioned the benefit to NOT using dummy plugs.
I use the swap-monitor trick to get them all going because, for example, my 5830 does 300 MH/s with the monitor plugged in. When I unplug the monitor to swap over to the 5850, the hashrate goes up to 304 MH/s.
I'm assuming dummy plugs would decrease all hashrates by 1%
I use the swap-monitor trick to get them all going because, for example, my 5830 does 300 MH/s with the monitor plugged in. When I unplug the monitor to swap over to the 5850, the hashrate goes up to 304 MH/s.
I'm assuming dummy plugs would decrease all hashrates by 1%
Cheaper and simpler dummy plug.
http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html
http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html
Even cheaper and simpler dummy plug:
http://blog.zorinaq.com/?e=11
I'm using 2 of them...
I would (personally) avoid this - if the wires cross somehow you're blowing the vid interface rather than your VGA converter. Use the VGA converter that comes with every video card, and just put the resistor between pins 1 and 6 - you only need one resistor (there is no benefit to 3, just costs 3x as much).
W
A standard HDMI port outputs digital in the block connector and standard analogue VGA on the cross connector. All a HDMI to VGA plug does in put the analogue connectors to a VGA pin format.
Analogue VGA outputs a Red, Green and Blue signal, known as RGB. All you need to do is put a resistive shunt across one channel to make Windows think you have a monitor attached.
Putting a resistor across the R, G or B channel (or all 3 if you mistakenly think it will make a difference) has the same affect whether you use the HDMI analogue connectors or the VGA adaptor analogue connectors. If you cross the pins on the HDMI to VGA adaptor it will have EXACTLY THE SAME AFFECT as if you'd crossed them on the HDMI connector.
The only difference using an adaptor has is that it may cost you more money.
Cheaper and simpler dummy plug.
http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html
http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html
Even cheaper and simpler dummy plug:
http://blog.zorinaq.com/?e=11
I'm using 2 of them...
I would (personally) avoid this - if the wires cross somehow you're blowing the vid interface rather than your VGA converter. Use the VGA converter that comes with every video card, and just put the resistor between pins 1 and 6 - you only need one resistor (there is no benefit to 3, just costs 3x as much).
W
a signal from resistor can blow the vid interface or the VGA converter? how does that work exactly?
OK, I would like to sum up what we know about dummy plugs. It has been bothering me quite a bit. Please correct and extend.
- Linux: no dummy plugs needed
- Win7: it is possible to force activate screens in display properties or change the EnableULPS registry entry
- WinVista: ?
- WinXP: dummy plugs or crossfire needed? did anyone manage to get it to work some other way?
Ive got Vista Ultimate running 2x cards, NOT in crossfire, 1 with a monitor hooked to it, and 1 with a dummy plug.
Ive also got Windows XP running 4x 5850s using dummy plugs, no crossfire cables.
OK, I would like to sum up what we know about dummy plugs. It has been bothering me quite a bit. Please correct and extend.
- Linux: no dummy plugs needed
- Win7: it is possible to force activate screens in display properties or change the EnableULPS registry entry
- WinVista: ?
- WinXP: dummy plugs or crossfire needed? did anyone manage to get it to work some other way?
if I use linux, I don't need dummy plugs right? just planning hardware right now
Correct. All mine are headless even.
if I use linux, I don't need dummy plugs right? just planning hardware right now
Correct. All mine are headless even.
if I use linux, I don't need dummy plugs right? just planning hardware right now
I dont get how you people get 2 cards running at all without the crossfire cable. I have 5 machines, each with 2 5970's in them. If I try to run them with a dummy plug and without the crossfire cable, they will run for a few minutes then the system will crash and it'll say there was a "Hyper Transport sync flood error" and I have to reinstall the drivers before all 4 cores are recognized again.
I use a KVM and 1 monitor.
Monitor goes into KVM
cables go from KVM into GFX cards of my computers
job done
I dont get how you people get 2 cards running at all without the crossfire cable. I have 5 machines, each with 2 5970's in them. If I try to run them with a dummy plug and without the crossfire cable, they will run for a few minutes then the system will crash and it'll say there was a "Hyper Transport sync flood error" and I have to reinstall the drivers before all 4 cores are recognized again.
Cheaper and simpler dummy plug.
http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html
http://www.overclock.net/folding-home-guides-tutorials/384733-30-second-dummy-plug.html
Even cheaper and simpler dummy plug:
http://blog.zorinaq.com/?e=11
I'm using 2 of them...
you the man.
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