Do the various PCIE slot splitter cards work at all? I'm considering getting several RX560's and upgrading my miner. The mobo it runs is an older Biostar A770E3 ( AM3 ) and has 2 1x slots and a single x16 2.0 slot. I would like 6 cards on that rig. Is it possible with those splitters? I read they do not work with Nvidia at all.
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PCIE slot splitter cards.
- Thread starter matt167
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No trouble using my generic Asmedia 4 way pcie switch with either brand.
However, your motherboard BIOS has to support "Above 4G Decoding".
Else nothing more than four cards will ever be stable, switched or not.
With my old Gigabyte Core2 Quad & a sixth GPU, it couldn't even boot.
Five sometimes works just well enough to be extermely frustrating, and
waste alot of time thinking you might be able to live without BIOS update.
But you lose more mining time to crashes than you can get from the extra
card. I highly doubt your old Biostar AM3 would receive such an update.
Switching requires only a 1x slot, and expands to four 1x UPCIE cables.
It doesn't bifurcate a 4x slot into four onesies. Bifurcate is like when you
split a 16x slot into a pair of 8x slots with optional SLI and all that junk.
A switch is a cheat that only talks to one card at a time. It can't do SLI
or Crossfire. But for mining, that is neither a problem nor a bottleneck.
However, your motherboard BIOS has to support "Above 4G Decoding".
Else nothing more than four cards will ever be stable, switched or not.
With my old Gigabyte Core2 Quad & a sixth GPU, it couldn't even boot.
Five sometimes works just well enough to be extermely frustrating, and
waste alot of time thinking you might be able to live without BIOS update.
But you lose more mining time to crashes than you can get from the extra
card. I highly doubt your old Biostar AM3 would receive such an update.
Switching requires only a 1x slot, and expands to four 1x UPCIE cables.
It doesn't bifurcate a 4x slot into four onesies. Bifurcate is like when you
split a 16x slot into a pair of 8x slots with optional SLI and all that junk.
A switch is a cheat that only talks to one card at a time. It can't do SLI
or Crossfire. But for mining, that is neither a problem nor a bottleneck.
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Cool, but even 4 cards is a good deal. I'm 99% sure it cannot do 4G decoding.. I'm currently running just 2x R9 270X 2gb in that box and they run 910 H/s in Cryptonight and 380 Sol/s in Equihash, but burn 350W combined at the wall, so roughly 50% of my profit goes to the power company, and if profits drop too hard, I have to shut down. RX560 should be close to that hash rate at 1/2 the power.
I also run an Optiplex 755 with a Radeon HD 7790 1gb which I've managed to make hash about 110 Sol/s in equihash but unstable if I push the clocks with Cryptonight.. Could I run 4 cards on that old rig? It's got 1 x16 slot and 1 x1 slot. It's my plex server and runs anyway.
I also run an Optiplex 755 with a Radeon HD 7790 1gb which I've managed to make hash about 110 Sol/s in equihash but unstable if I push the clocks with Cryptonight.. Could I run 4 cards on that old rig? It's got 1 x16 slot and 1 x1 slot. It's my plex server and runs anyway.
Derfnofred
Gawd
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Not sure how much you can play with the bios, Matt, but unless you're going to populate all the parts of a switch, it's definitely worth undervolting the 270x's like mad and seeing what clocks you can hold onto. I have lost very little hash speed (essentially none) by dropping the voltage from 1.2V to 1.066 V on my 280x from the stock 1020/1500 to 970/1500. Tidy drop in temperatures, too. Probably have a bit more room power/clock-wise to get that profit/kwh up.
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The 4in1 PCIe splitter riser cards "work" equally for NVidia as they do AMD. Mailiya and Ubit brands work well for me with my 9 card 1070 Ti rigs.
As for the 270x's - definitely undervolt. My old 270s could be volted down to ~1.00v and maintain 1000/1400 and ~400Hs in XMR.
As for the 270x's - definitely undervolt. My old 270s could be volted down to ~1.00v and maintain 1000/1400 and ~400Hs in XMR.
I'm currently undervolted 16% in the AMD software. Any less and things get wonky. I'm running 1050/1500 and any less the hashrate takes a hit, and any more the hash rate takes a hit. These are OEM Dell blower cards. Is it really worth running them along side 2 other RX560's?
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The 270X was basically a 7870 on roids, so using it as a base and changing the wattage to ~110w and the speed to 450Hs i see that it is profitable at .12c/hWh.
If you are paying more than 12c/kWh or you are too far over 110wm, you may be breaking even though.
If you are paying more than 12c/kWh or you are too far over 110wm, you may be breaking even though.
Yeah, my calculations are that they do run in the green, but barely.
If I just dumped the 270's in favor of even a couple RX560's, the 560's make a little less, but take a lot less power so they actually make a lot more ( double by NH calculations ).. However, I'm going to run them while they are in the green, but will add RX560's into the mix as my mining profits allow. I've currently got one coming to expand the other box.. The end game right now is 6+ RX560's across both boxes.. My main gamer is probably going to get a 1070+ next month when my funding allows so the MSI Armor 1060 6gb will get kicked back and take up a single position on one of the miners, although I mine it currently anyway.
If I just dumped the 270's in favor of even a couple RX560's, the 560's make a little less, but take a lot less power so they actually make a lot more ( double by NH calculations ).. However, I'm going to run them while they are in the green, but will add RX560's into the mix as my mining profits allow. I've currently got one coming to expand the other box.. The end game right now is 6+ RX560's across both boxes.. My main gamer is probably going to get a 1070+ next month when my funding allows so the MSI Armor 1060 6gb will get kicked back and take up a single position on one of the miners, although I mine it currently anyway.