[QUOTE=flashjh;410918]What system can host that many cards?[/QUOTE]There's a fair number of motherboards that will support quad video cards. [URL="http://www.geforce.com/whats-new/guides/how-to-build-a-quad-sli-system#2"]This page[/URL] has a more restrictive list of boards that support 4-way SLI (as in 4 identical cards working together) as opposed to just getting 4 random cards working in the same system. Major considerations include a case that supports (at least) 8 slots (rather than the usual 7), and a very hefty power supply.

[QUOTE=James Heinrich;410926]There's a fair number of motherboards that will support quad video cards. [URL="http://www.geforce.com/whats-new/guides/how-to-build-a-quad-sli-system#2"]This page[/URL] has a more restrictive list of boards that support 4-way SLI (as in 4 identical cards working together) as opposed to just getting 4 random cards working in the same system. Major considerations include a case that supports (at least) 8 slots (rather than the usual 7), and a very hefty power supply.[/QUOTE]

Indeed I've done it before, but cooling is the biggest problem. Just wondering what the configuration is, but the added TF or LL capability is surely a good thing.

For 8 cards, I use SuperMicros dual Xeon E5v3 GPU server systems which use 16x PCIe lane switches.

For this system and most 4 card systems I use i7 5930s (44 PCIe lanes more cost effective than the 5960 8 core), this particular system is a gigabyte X99-UD3P which will give me Qty 4 PCI 3.0 8x slots. For most work this is ok but I'm still researching why mfaktc/o are slowing down with less lanes despite not needing much data transfer bandwidth. I use a case that has space below the 4th slot for a double slot card but in reality there are many cards that only need 1 slot once on water blocks. Corsair AX 1200 or 1500 power supplies round out the requirements.

I think it would be impossible to get decent performance on air but with liquid cooling card density is less of an issue. The random cards come from what I have been able to pick up cheap on clearance from the local MicroCenter.

[QUOTE=airsquirrels;410908]I have betrayed AMD and added an NVIDIA Rig to the mix with an array of cards (690, two 980s and a Titan X). Eventually these will be doing CudaLucas LL work but I have them also contributed to LLTF for now. Should add some extra boost.[/QUOTE]
Ha! Now you have 5 GPUs (because 690 has two) and you can try CRAPLLA, or how it was called! :razz: :razz:

[QUOTE=LaurV;410954]Ha! Now you have 5 GPUs (because 690 has two) and you can try CRAPLLA, or how it was called! :razz: :razz:[/QUOTE]

:smile: :tu:

User dh1 has found a factor! Hooray!

This means I have regained my status as the top TFer on GPU72, excluding everyone who has found at least one factor. :smile:

[QUOTE=cuBerBruce;410982]User dh1 has found a factor! Hooray!

This means I have regained my status as the top TFer on GPU72, excluding everyone who has found at least one factor. :smile:[/QUOTE]

Congrats! Thanks for the help :smile: (^^ that's good stuff right there)

You only have ~150 expos, when it is supposed that you find a factor every ~73. You are still "in the distribution". Be patient, if your hardware is not in the weeds (i.e. giving random results), then the factors will come... will come...

[QUOTE=LaurV;411036]You only have ~150 expos, when it is supposed that you find a factor every ~73. You are still "in the distribution". Be patient, if your hardware is not in the weeds (i.e. giving random results), then the factors will come... will come...[/QUOTE]

A few days ago, I had my teeny tiny GPU do [url=http://www.mersenne.ca/exponent/73380271]M73380271[/url] as a sanity check. I wasted 5 hours, but the known factor for that exponent was found, so I believe the hardware is fine. (And of course, I had run the mfaktc self-test before doing any assignments.) I think Chris just keeps giving me bad assignments.

[QUOTE=cuBerBruce;411041]I think Chris just keeps giving me bad assignments.[/QUOTE]

Well, you know he's hogging the good ones for himself, right? :smile:

I'm now 0 for 200 in factoring assignments. 188 TF assignments (177 from GPU72, 11 from Primenet), 12 P-1 assignments.