LOL, I didn't know people were running those kind of cards, I'm almost wasting as much GHzD/D. Not that it matters, every bit counts.
I'm running my HD7950 at 265GHzD/D during the day and 400GHzD/D at night, because I can't stand the screenlag/video stuttering.

Y'all making me feel guilty so I've picked up 1THz-day of work.
I also noticed that the assignment-preview showed me 38M,69-70 but the assignments I got were 36M,70-71 (as [i]monst[/i] [url=http://www.mersenneforum.org/showpost.php?p=387931&postcount=3136]said a few posts back[/url]).

LOL, I guess I can do some too... I have almost 700 GHz/days of power I have at the moment, you want the default, to 71 bits on what makes sense?

[QUOTE=monst;387931]There is something funky with the gpu72 website with regards to getting DCTF assignments...[/QUOTE]

Thanks for pointing that out -- one constant in the javascript that does the "LG72D" thing. Should be fixed now (you might need to clear your cache to pick up the new version).

And, so everyone knows, with the firepower which has suddenly come forward what makes the most sense (in my opinion, and currently codified on GPU72) is simply lowest exponent, regardless of it's current TF level. This will mean initially 70 to 71.

But, of course, anyone who wants to only go to 70, that's cool too.

We'll already have about 20,000 candidates at 70 which we can return if needed, but it's looking very unlikely we won't immediately start to pull ahead of the "churners".

[QUOTE=VictordeHolland;387981]LOL, I didn't know people were running those kind of cards, I'm almost wasting as much GHzD/D. Not that it matters, every bit counts.
I'm running my HD7950 at 265GHzD/D during the day and 400GHzD/D at night, because I can't stand the screenlag/video stuttering.[/QUOTE]

I also stop mfaktc on my primary card (almost back from RMA, actually) when using my home desktop for the same reason. At work I use the on-board Intel graphics so the two GTX 580's in that box can stay flat out 24x7.

[QUOTE=chalsall;387977]Thanks for all the cycles everyone; looks like we'll be able to squeak by without releasing anything at less than 71.

I've also brought a EC2 instance online for a while; 2 * 2050 Titans at ~520 GHz-d/d (aggregate) for ~13.5 cents an hour! :smile:[/QUOTE]

How do you do this???

[QUOTE=Primeinator;387992]How do you do this???[/QUOTE]

Spot instance pricing on Amazon EC2. One availability zone in us-east-1 has cg1.4xlarge for about $0.135/hour, or about $3.25/day.

[QUOTE=Mark Rose;387995]Spot instance pricing on Amazon EC2. One availability zone in us-east-1 has cg1.4xlarge for about $0.135/hour, or about $3.25/day.[/QUOTE]

Yup. Just sign up to EC2, spin up an instance which can support NVideo CUDA (there are a bunch free ones; choose your faviorate distro) on a cg1.4xlarge instance type, install CUDA (and apply security updates, etc).

Next, create a new 1GB volume, and amoung other customizations change /etc/fstab to include a line which reads "/dev/sdf1 /home ext4 noauto,noatime 1 0", and then attach this to your instance (by default it will be "/dev/sdf"). Use "fdisk /dev/sdf" to create a single linux partition, and then "mkfs.ext4 /dev/sdf1".

Now, copy (with the archive flag) the existing "/home/ec2-user" directory to "/tmp/" Lastly "mount /home" should bring the newly created partition online. Move (or copy) the "/tmp/ec2-user" directory to "/home".

"shutdown -r now", log back into the instance, and execute "sudo mount /home". Make sure the new home partition mounts correctly.

If it does, then install all your desired mfaktc software in two seperate directories (including any submission / fetching spiders desired, and create the related cronjobs) and give it a go. Launch two mfaktc instances (the second with "-d 1"). You may also want to install an instance of mprime as well.

If everything's working the way you want then "Create Image" from the "Instances" tab. This will create a custom AMI which you'll boot from in the future (thus avoiding the need to install CUDA and the software each time.

Note that, importantly, the AMI file system is ***NOT*** preserved between instance creations; this is the reason for the extra volume created for "/home" -- mounted volume's are preserved.

Oh, and know that spot instances can go away at any time without notice. But, they're dirt cheap; I usually bid at $0.15 per hour, and often have one (or more) instances up for many days paying on average $0.135 an hour.

It's actually relatively easy to do.

:goodposting:

That is more competitive with hardware @home than I thought!

The Amazon EC2 "g2.2xlarge" consists of:
Intel Xeon E5-2670 (Sandy Bridge)
15GB RAM
NVIDIA GPU with 1,536 CUDA cores

At $0.135/h = ~ $100 a month.

Buying+running hardware @home in Netherlands
Quadcore (Core i5) €160
16GB DDR3-1333 RAM €135
GTX770 (1536 CUDA cores) €230
Motherboard €65
PSU €50
--------------------------------------------
Initial investment: €640 or $800 (assuming you have a spare HDD and case)
running costs (very crude way)
CPU TDP 84W + GPU TDP 230W = 314W
314W * €0.20/KWh = ~€0.06/h or $0.075/h

Breakeven is after $800/($0.135/h-$0.075/h) = 13,000+ hours, that is 1.5 years!

Some remarks:
The throughput of the home system is higher. (Xeons have lower clockspeed than the i5s and Tesla cards also have lower clockspeeds than their consumer counterparts. And the home system has some residual value.
On the other hand a g2.2xlarge Spot Instance in EU (Ireland) is only $0.0801/h at the moment, which is very close to the $0.075/h running @home!


Question: Can EU residents start Spot Instances in all regions? In that case you could just pick the cheapest region.

[QUOTE=VictordeHolland;388019]Question: Can EU residents start Spot Instances in all regions? In that case you could just pick the cheapest region.[/QUOTE]

Yes.

For me, actually cheaper than the electricity to run a G580.

[QUOTE=VictordeHolland;388019]
Breakeven is after $800/($0.135/h-$0.075/h) = 13,000+ hours, that is 1.5 years!
[/QUOTE]

Yep! My electricity cost makes the break even point almost as much with the higher US dollar at the moment. But that's if buying new hardware. If you get "free" electricity, and buy old GTX580's at $100/each and pop them into machines, the recovery time is one month. I need to find more such machines lol

[quote]
On the other hand a g2.2xlarge Spot Instance in EU (Ireland) is only $0.0801/h at the moment, which is very close to the $0.075/h running @home!
[/quote]The g2.2xlarge is not such a good value. You only get a single GPU at 240 GHz-d/d instead of two GPUs at 280 GHz-d/d. For mfaktc, the g2.2xlarge's fair value in comparison is $0.05/hr.

[quote]
Question: Can EU residents start Spot Instances in all regions? In that case you could just pick the cheapest region.[/quote]The cg1.4xlarge is only available in us-east-1 and eu-west-1. Of those, only in one available zone in us-east-1 has the spot price been hovering around $0.135.