Anyone using PCI-e Multipliers?

[RickJamesBTC]

I have run across this listing, and I'm wondering if it will function properly mining with a lot of cards, using the BAMT linux disto, or any other linux setup.

Are there any limits to the number of GPUs per system? Will running 4 pci-e 1x cards per slot x 5-6 slots overload the pci-e lanes?

http://www.ebay.com/itm/PCI-e-express-1X-to-4port-1X-16X-multiplier-riser-card-cable-4-diy-bitcoin-miner-/321248295196?pt=LH_DefaultDomain_0&hash=item4acbe3f91c

I was sticking to 5 gpus per system, on the cheap base systems I have (gd45 mobos, 8gb ram) but the idea of turning that into 20-25 gpus per base unit would be very entertaining! (Not that I could find enough GPUs to fill it at this time)

[grue]

I have run across this listing, and I'm wondering if it will function properly mining with a lot of cards, using the BAMT linux disto, or any other linux setup.

Are there any limits to the number of GPUs per system? Will running 4 pci-e 1x cards per slot x 5-6 slots overload the pci-e lanes?

http://www.ebay.com/itm/PCI-e-express-1X-to-4port-1X-16X-multiplier-riser-card-cable-4-diy-bitcoin-miner-/321248295196?pt=LH_DefaultDomain_0&hash=item4acbe3f91c

I was sticking to 5 gpus per system, on the cheap base systems I have (gd45 mobos, 8gb ram) but the idea of turning that into 20-25 gpus per base unit would be very entertaining! (Not that I could find enough GPUs to fill it at this time)

for $80 you can get a whole new motherboard with 4+ slots.

[RickJamesBTC]

Yeah, but motherboard, plus ram, plus cpu, plus thumbdrive, plus setting up and maintaining each system becomes a pain as the systems grow. If switching from risers to these lets me 4x the number of cards per system, that would be amazing.

[RickJamesBTC]

Also, each mobo requires an atx connection so more power supplies or less organized cases

[Lucky Cris]

Hi RickJamesBTC,

You ever found that answer to the number of GPUs per system? Also, what are your thoughts about powering a 10 GPUs?

[RickJamesBTC]

Nobody seems to have tried these, so who knows.
As for power, if all you need is LOTS of +12, it is easy to do. I have three phase power personally, so I could buy big surplus 4kw-6kw 12v power supplies and run the cards directly from them. Building them as individual systems has led me to just use pc power supplies, but being able to run a large increase in cards with far less atx requirements would be good motivation to try that.

[1632008]

It would definitely be wonderful if 20-25 gpus could work in a single system.
However, this is not easy at all. There are various limits of gpu numbers coming from bios, OS, drivers, power delivery...
Check this thread for reference:
https://bitcointalk.org/index.php?topic=64450.0

was sticking to 5 gpus per system, on the cheap base systems I have (gd45 mobos, 8gb ram) but the idea of turning that into 20-25 gpus per base unit would be very entertaining! (Not that I could find enough GPUs to fill it at this time)

[RickJamesBTC]

Oh well, looks like amd can't be bothered.
Well if they ever release a driver package that can handle many gpus, I hope these are still available.

[roy7]

What's the max number of cards for nVidia drivers? With the hash/power ratio of Maxwell, it'd be interesting to try this if nVidia allows > 8.

[nybbler905]

It would definitely be wonderful if 20-25 gpus could work in a single system.
However, this is not easy at all. There are various limits of gpu numbers coming from bios, OS, drivers, power delivery...
Check this thread for reference:
https://bitcointalk.org/index.php?topic=64450.0

was sticking to 5 gpus per system, on the cheap base systems I have (gd45 mobos, 8gb ram) but the idea of turning that into 20-25 gpus per base unit would be very entertaining! (Not that I could find enough GPUs to fill it at this time)

That does not count the hard coded to WinBlows 9 screen max.  I mean 9 monitors so dual head cards can count as 2 screens.  I'm not sure what ( if any ) Linux distros may have as a limit and the original eBay actually can only do 2 cards per that adapter.  The white for one type and the black for PCIx16 cut down to the x1 speed ( read the fine print people!! ) so you would need 2x of them per slot to only doubble your GPUs and most likely 1 dummy plug on all but what you actually look at to get up to 8 ( best guess guestimate ) cards per average 4 pci/pcix16 mobo out there.  Still... good luck actually finding that many that will play nice together.

[duniek]

in windows everything works OK

I will test it at mining later

[gtraah]

I wonder how R9 290x Cards will hold up since they use much more power..

Also what would happen if you fill each slot with 4 x PCIE multiplier

over 20 GPU's Then make them all R9 290x and I just dont see it happening something will pop lol Id lover to see it go though 

[duniek]

I am using usb risers so power of pci-e doesnt matter for me.

Anyway, with usb risers and without molex, multiplier doesnt work.
So you have to plug molex connector.

[VirosaGITS]

Wow thats alot of wiring for 1x4 gpus. I'd want to see a pic of setup of this with 7-8x4 gpu motherboards, hah!

[nybbler905]

With the pics, i admit my other statement is completly WRONG.  The ' other ' multipliers I could find ( some on eBay, the actual ICs on TI.com ) were mostly 2x with an option of what speed and thus a colour difference in slots IF it had 4 slots.  Just looking at the pic of the actual card, there are more pins on that one multiplyer IC ( over 40ish in quad flat pack ) and it definitly looks like it actually talks to each slot individually.  I'd love to find out the hard coded limit ( if any ) for GPUs with that kind of thing.

[duniek]

dont have any proof for now but, I make rig today  - 4x 270x  direclty from motherboard (asrock btc) and  3x 280x (on multiplier).Everything works fine (speeds 600/720/720khash @ 280x and 450each from 270x) this 600khash thing is normal for me (even without multiplier one card is slower sometimes)


ghetto mounitng and bad nokia e70 pic (also I have bad light in mining room)

[primer10]

cool, thanks for the info!

[duniek]

OK its done

I think hashrates will be the same as plug directly to motherboard.

On 3x 280x i get 590/690/690 (I hate 280x personally) sometimes everything work ok 700-720 each card, sometimes one get slower hashrate (doesnt matter multiplier or motherboard)- I cant explain that

anyway
I change mining on keccak SHA-3 and now everything the same.

Later I will try to put 4x 270 on multiplier and 3x 280x on mobo.