Topic: Any word on amd vega hash rates? - page 46. (Read 202748 times)

Please at least attempt to contribute to the conversation. 


Thanks for the real-world experience.  I don't know if I'm down to start diy'ing my own wires, but I'll at least keep an eye on them.  I did a little further combing and found an old post on tomshardware, which may or may not be true?  Either way, it's interesting.  I would love it if someone threw a mythbuster up on youtube for this one. 

""
Johnny & the group,

Have learned several interesting facts about the PCI-E plugs and power after researching it this past week, that is worth sharing

The PCI-E connecter has 6 pins. They are not all used for power. For the 6 pin connector, Pins 1 & 3 are 12V & each can carry 8 Amps. Pin 2 by spec is not connected, although some PSU manufacturers do add a 12V line there. Pins 4 & 6 are Com return lines. Pin5 is Com for sensing. Using 2 lines, you get 12V*8A*2= 192Watts, much over the required 75Watts. With an 8 pin PCI-E connector, 2 Com lines are added (4& not a 12V & Com. There, Pins 1,2,3 are 12V, Pin 4 is a Com for the 8 pin connector sensing, Pin 5,7,8 are Com return lines, & pin 6 is for the 6 pin connector sensing. Using that config, 12V*8Amp*3=288 Watts, much over the required 150Watts.

Since Mar 2005, the molex pins are required to be "HCS" rather than "Std", which each carry a max of 11Amps. So properly made, an 8 pin PCI-e can supply 12V*11Amps*3lines=396Watts of power for the graphic cards.

Ther aren't 4 12V pins on the 8 pin connector, only 3, and 2 leads are used for sensing the connector type.

The other limiting factor of course is the width of the PCB lines on the graphics card, each typically carrying 1-2 Amps. That would also determine how much power it could carry to the graphics electronics.
Also worth noting Scott Meuller in his latest 19th Ed of "Upgrading and Repairing PCs" has this information incorrectly listed.
""

Hey there. Is there any powerplay for the vega 64 AIO ? I have tryed the 1100 powerplay with the registry editing and it didnt work for my cards and i cant find 1 for the water cooled gpus i own. I am in need of serious help cuz right now with wattman or msi afterburner oc i get the 2080 hashrates but i draw 1800 w at the wall lolz . Any help would be very apreaciated. Thanks.

In the current market, would you pay $525USD per Vega 56? From a retail outlet.

Australia has a little lag compared to US supply / demand markets.

For reference I paid $430USD each one week ago.

Two things... 
1) You can actually do what you are looking for with a windows script...  no Devcon.exe is required:  http://vega.miningguides.com/p/auto-run-miner-without-hashmonitor.html
2) You can get Devcon.exe direct from Microsoft without an extensive installation by following the method here: (first time I posted this link bitcointalk said it was a suspicious link and took it out... not sure why but I have edited the post to break the link into two pieces... (Just remove the spaces):     https://networchestration.wordpress.com/2016/07/11/       how-to-obtain-device-console-utility-devcon-exe-without-downloading-and-installing-the-entire-windows-driver-kit-100-working-method/

 

Where Can I find Devcon.exe? Where's the file location I mean. Please help.

Down the memory clock back to 800 maybe 900MHz and do a test. I have this same issue whit 1000 and 1100 reg mods. When miner start driver crashes the system.

Use reg mod to set voltages and overdriveNtool to set de clocks for core and mem.

My vega cards does't start without the 2 8pin conector pluged, so I'm use 2x 700W 80's plus PSU (Evga and Thermaltek) for cards and an old Seventeam (no 80 plus) 420W for the system (mobo, cpu, ssd and 2 risers), 4x Vega56 + 2x RX580 arround 1000w Total system power.

Of course. I expect Your next move to be fixing another car on top of Your car so You can drive 10 persons.

if you undervolt  it should be ok but not too safe  2x8pin cable can do 360w  can go bit higher but check if it not getting hot

what you could do is add a wire from a molex cable , it s what i do, i manually connect a wire from the molex +12V and plug it in on 1 of the 3 +12V, and put some tape so the wire cannot get out by accident

problem with vega even if you undervolt to 150w it has a lot of pics what use more than 150w

i tried 2x vega on a 750w psu  when it average use less than 550w , time to time the psu was shuting down (so get up to 700w?)

i put 3x vega on a 850w (there are only 4x 8pin connector) i made 2 extra 8pin  my self used bridge + all molex connectors better use to much wires than too less

Dual I understand.  Certified, I do not.  The whole world of cabling is new to me, however.  Is there a trusted certification authority or something?   Also, I haven't been able to find any 8-pin to 2x8-pin that seem to be from reputable vendors.  Everyone seems to make 6-pin ones, but the 8-pin ones seem harder to find.  Am I missing something or are larger vendors doing this intentionally? 

Per my little research..
Credit to stackexchange question.. "Is there any limit on how many SATA power connectors i can extend" (superuser). 
Helpful link was wire gauge to current rating..  Seems 18 gauge for short runs can max out at 16A, 16 gauge at 22A, which translates to roughly 12*16 and (or) 12*22. 
As per their nifty chart, they're saying (as conservative figures) for max load for  the different wires:

Gauge	Max Load
18	192
16	264

 
I could definitely be wrong.  So eat with salt.  But since everyone's undervolting, if they're using the 18 gauge, they're probably somewhere near the top end of the allowable range.  If the cards or software fault, however, and they start pulling 250+ from the psu (does anyone know what it pulls w/o the undervolt--has anyone measured the wire?), I guess it's anyone's chance if a fire starts/they begin to melt?  For posterity and the curious, I've got vega64 lc's running on these cords. 
If anyone's got wiring like this, but is NOT undervolting, I would be curious as to how long they've been running, how many watts they've been pulling, etc.  It's hard to find solid information out there. 

How did you come to this conclusion?

That's a bold statement. Have you got any proof/source to back it up? Arguably there wouldn't be any need for powered risers (or additional molex+sata connectors on the Onda boards) if that were the case...

I had similar problem, Seasonic PSU 1200W but only enough connectors for 4 vega.
PSU have 2 cables for CPU so I bought 8pin CPU to 2x8pin PCIe adapter, first one I have ordered had wrong design, it delivered voltages to gpu in reverse (12v where should be ground and vice versa). Find out that just after I plugged it to gpu. I had more luck than brain because PSUs protection kicked in and nothing was damaged. So I cut wires and solder them as they should be and it works. On ebay almost all CPU to PCIE adapter I have found have wrong wiring, correct way is to crossover wires.
https://imgur.com/a/yOjz2
Wrong type, double price
https://imgur.com/a/KDVuz

On VEGA, only the blower fan is powered from the PCI slot.
The fan uses 28W at full rpm.
Typically, you will see around 15 - 20W during normal use.

Damage the cards and burn the place down by providing less power?...

The only logical explanation out of this would be if that forced the cards to pull more power from the PCI-E slot.

In any case, thanks all for your suggestions. I've ordered a couple of "8-pin to 2x 8-pin" splitters and a few "6-pin to 8-pin" adapters. Should hopefully do the trick.

Well, my vega is on its way but I have learned a lot and try to be ready when it come
May I suggest you to check this site? http://vega.miningguides.com/
there is very detailed guide how to make it work, I will do as described here

Yeh, my 750 and 850 G2/G3's come with 2 8pin->2x 8pin cables. So, I've been using those for the vegas.

Uh, how do I politely say I don't think so?  I'm using splitters on every Vega I own and quite a few of my 1080 Ti's.  But let me quickly add that because power is expensive where I am, I undervolt and look for max Sols/w or max H/w.

And I've been doing this for some time so if a fluctuation was going to burn the place down, would have probably happened.

Go to eBay, get the splitters, like this one:

https://www.ebay.com/itm/1-Pc-PCI-E-6-Pin-Femal-To-Dual-8-Pin-6-2-Pin-Card-Power-Adapter-Cable-PCIE-PCI/222615689892?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

They work well.  I've used them on 1080 Ti and Vega (but I undervolt, I don't go crazy with TDP +120 or anything like that).

But if I were you, I think would think about a server PSU, maybe the DPS-2000 or DPS-2500 and a price-technology.com breakout board, 6-pin cables to PCIe risers, 6-pin cables to (2) 6+2 pin splitters for GPU. You'll need a pico psu as well and a 240v outlet OR a step-up transformer (search "ELC step up transformer" on eBay).

All of that is less that the EVGA 1600 PSU.  Not that I have anything against EVGA - that's a solid PSU.

That's no different than using any splitter cable.  The issue isn't splitting, the issue is overloading of the PSU cable.