Curtis and similar GPU build

[Manpowre]

I have noticed from 26th of june to today 7th of august Dr Curtis Cooper has checked 771 primes, probably world record prime enabled here right ?

That means about 18 numbers checked per day in average.

Lets say each Nvidia Titan can do one number in 3 days, = 3 titan cards for each number at the LL test level we are at right now. that means we need 54 cards at 1000 USD each to compete + 14 machines to host those cards (4 cards in each, with each machine cost 1500 USD). Total investment of 75 000 USD.

If we can get hold of used Nvidia 590 boards, each board does a little better than one Titan card, so around 50 590 boards or something, we can setup similar setup for 13 machines, but used 590 boards can get purchased for 250 USD each or less = 33 500 USD.

So, 13-14 machines is what it takes with the right GPU to compete with Dr Curtis Cooper using GPU's.

Interesting.

[ET_]

Originally Posted by Manpowre

I have noticed from 26th of june to today 7th of august Dr Curtis Cooper has checked 771 primes, probably world record prime enabled here right ?

That means about 18 numbers checked per day in average.

Lets say each Nvidia Titan can do one number in 3 days, = 3 titan cards for each number at the LL test level we are at right now. that means we need 54 cards at 1000 USD each to compete + 14 machines to host those cards (4 cards in each, with each machine cost 1500 USD). Total investment of 75 000 USD.

If we can get hold of used Nvidia 590 boards, each board does a little better than one Titan card, so around 50 590 boards or something, we can setup similar setup for 13 machines, but used 590 boards can get purchased for 250 USD each or less = 33 500 USD.

So, 13-14 machines is what it takes with the right GPU to compete with Dr Curtis Cooper using GPU's.

Interesting.

You forgot the heat dissipation and the energy consumption...

Luigi

[Manpowre]

Originally Posted by ET_

You forgot the heat dissipation and the energy consumption...

Luigi

True, I didnt even want to think about it, especially with 590 boards which consumes 375w per board. hehe..

[kracker]

Originally Posted by Manpowre

True, I didnt even want to think about it, especially with 590 boards which consumes 375w per board. hehe..

54 Titan=13500W

I have enough with my 400W med-end computer! lol

[henryzz]

Originally Posted by kracker

54 Titan=13500W

I have enough with my 400W med-end computer! lol

With that sort of power budget I imagine you could run a fleet of around 200 low power quads(800 cores). I doubt a titan can match 16 cores(at 2 Ghz for a 4765T)

[Primeinator]

Originally Posted by henryzz

With that sort of power budget I imagine you could run a fleet of around 200 low power quads(800 cores). I doubt a titan can match 16 cores(at 2 Ghz for a 4765T)

But more difficult to store...?

[TheMawn]

I think one might be better off getting GTX 760's or something instead. Cheaper and cooler for the amount of work they would do.

Now, I know very few motherboards appreciate trying to do 4-way SLI but the cards don't have to be in SLI, so can any motherboard with 4 GPU slots (spacing permitting) run four GPUs?

Also, make sure to count the CPUs you'll be hosting as well.

[kladner]

Originally Posted by TheMawn

..... can any motherboard with 4 GPU slots (spacing permitting) run four GPUs?.....

Cards which exhaust out the back instead of inside might make it. But really, that kind of rig cries out for water cooling.

Spacing is really a problem, too, as most high-end cards are double slot, at least. I think you could get three on my board, but keeping two dump-heat-inside cards cool is already a challenge. The fourth slot is too close to a bottom-mount CPU in a mid-tower case to put a dual-slot card in.

Then there's this. "Solution for those who has the desire"(SIC!) (and whose children is learning!) Note photo of 4x GTX 480 cards in SLI. Kind of dates it, eh? (Diesel generator not included.)

[LaurV]

Originally Posted by TheMawn

...the cards don't have to be in SLI, so can any motherboard with 4 GPU slots (spacing permitting) run four GPUs?

Yes, if it has 4 pcie slots, with enough space between. Unfortunately a good GPU takes over 2 slots ("over" like in "more than", not like in "to take over", they are usually 2.4, 2.6, 2.8 slots, air cooled, and this especially for Asus cards, their DCII line, etc), and there are not so many mobos around to accommodate the space of 12 slots in 4 connectors. You need to go water cooling for that.

Edit: about the ROG expander: Don't buy it! It even doesn't work with their own cards, all are more than x2 wide! In fact, the last photo from that gallery is the stupidest thing I saw in a long-long time: the mobo they used in the photo has already 4 slots, which you can't use because you placed the expander on top of them, which expander, of course, has just 4 slots too... (placed at the same distance between each other )

This photo reminds me of the RS232 "gender exchangers": that was a piece of cable about 10-15 cm long, with 9-pin D-Sub connectors at both sides, the idea was that if you have a "male" connector, you plug the "gender exchanger" into it, and you have a "female". Or viceversa. Of course, they were delivered in both "crossing" and "non-crossing" - who knows the serial protocol of exchanging Tx and Rx wires, knows what I am talking about - some serial cables you buy from the shop are crossed, some are straight, and you find this out, especially in China, only after you bought the cable and went home with it. So, the company I was working for (that is 20 years ago) produced "gender exchangers", "crossed" or "straight", a good tool in the hands of any IT technician. This toy, logically, must have either two male connectors, or two female connectors (think about it! or just google "gender exchanger rs232" and look to the pictures). Some "genius" from the project management of that product considered that if you want to "exchange" the gender, then you need to have a small piece of cable with different connectors at the ends. They produced few lots of 10k pieces each until someone realized that the "product" was not useful for anything, except only to extend any serial cable with few centimeters. This is not a joke, some of these "gender exchangers" still can be bought today, a small piece of cable with a male connector at one side, and a female at the other side. Nice! Same as the Asus' expander above... ROFL...

[Manpowre]

I've found high end motherboards large enough to host 4 cards easily. With the air flowing out in the back, and a server cabinet with air intake in front of the cards, it will work. Offcourse the CPU cannot do Prime95, it has to host the processes for the GPU's. and a 1500W powersupply, 16gb memory 1600 speed or faster..

would work.. I actually have 2x 590 boards coming to me in a few days,.. trying to get hold of 4 more.. If I get 4 more, I will order a machine specific for this.. only 1500 USD for the machine anyway.. and see how the machine can perform with all peices together..

[Manpowre]

About GTX760.. or 780..
The card has 1/24 DP performance.. for the price, the 580 and especially 590 is way better.

One 590 outperforms Nvidia Titan over number of days.. as a single thread offcourse Titan is the best, but running Ghz days, 590 outperform it.

and the price for these boards used now.. really bang for the buck.