Hello. Currently I use a GTX 670, but I was wondering if it was possible to add another card other than the 670 for the sole purpose of crunching.

For example, if I were to buy a GTX 295, and add it to the motherboard, would Boinc be able to give another GPUGRID task to it, even though I can't use the 295 for SLI mode?

Sorry for the poor wording, but I was wondering how this works. If possible, I would also like to hear some experiences and stories with this.

Thanks in advance.

I have a 680 and 570 running in mine with no problems. Probably as long as the driver you use lists both cards as supported, I would think it would work.

I would suggest avoiding the GTX 295. These can be troublesome on their own, and are several generations behind a GTX 670 (170W TDP). A bit of a challenge to Boinc, the drivers, the project, the system and the user. I would suggest a GTX470 or something more recent. As more GeForce 600 cards are due to be released in a week, wait for the release. At the very least GeForce 500 prices will fall.
Even the sweetest performing GTX295 comes with high running costs (289W TDP).

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I agree with everything above but can say that it does definately work as I just took my GTX295 off a rig where I was running it alongside a GTX480 with the with the 301.42 driver. I did not have any problems getting work or completing work (was overclocking and could return long WUs in less than 24 hours). If you still have interest in a GTX295 drop me a PM and we'll see how cheap you can get it from me :-)

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Thanks - Steve

Currently the GTX660Ti looks like a sweet deal for GPU-Grid: should be about as fast as GTX670, but is significantly cheaper.

MrS

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Scanning for our furry friends since Jan 2002

If youre going to buy an older card, why not go with a 460. Its a fermi card, and they have been showing up on ebay for $75-85. The 460 is a better choice than the 470 as it is more efficient on a power to performance scale. A 560 would also be a good choice since they are going for about $100-$130 on ebay now.

If youre going to buy an older card, why not go with a 460.

The GPUGrid client can use only the 2/3rd of the shaders of any CC2.1 card.

The 460 is a better choice than the 470 as it is more efficient on a power to performance scale.

While it's true for gaming, it's false for GPUGrid.

A 560 would also be a good choice since they are going for about $100-$130 on ebay now.

A GTX 570 or 580 would be even better. But it's highly not recommended to buy older GPUs for crunching. At the moment the best choice considering the price/performance and running cost/performance ratio is the GTX660Ti.

The 'GeForce GTX 660' is supposedly due out soon. Expected specs are GK106, 960Cuda Cores, 980MHz, 1033MHz, 192-bit, GDDR5, 3000 MHz, 140 watts (specs to be taken in mildly saline solution).
If speculated specs are accurate-ish, expect the performance to be around 75% of a GTX660Ti, which would make it an excellent bang for buck mid-range card for GPUGrid.
Of course the release date and specs are not actually known. Ditto for performance, but I would expect it to work straight out of the box, as was the case with the GTX660Ti and GT640 (Kepler).

You can read about the GTX 660 OEM (GK104) at AnandTech

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The rumored GTX660 (non-OEM) has to be significantly cheaper than GTX660Ti, though, as the performance difference is rather large.

MrS

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I am running a GTX580 with a GTX660Ti on the same PC without issue. Both use Driver 306.02.

Now that I have them settled in I am generating over 400k points per day.

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Rumor has the GTX 660 from around $229/£145/185 Euros; 75% of a GTX660Ti. So it's fairly sweet, and these will be the only mid range GeForce 600 cards to date (one 6-pin power connector).

There is inevitably going to be a wide variety of these cards to chose from, so some will not be half as fast as a super-clocked GTX660Ti (which out-performs some GTX670's), while others will be within 20% of a reference GTX660Ti. Prices will obviously increase from the reference model, but WRT GPUGrid, performance will rise almost linearly from the GTX 660, through the GTX 660Ti and GTX670.

Any of these cards should sit well besides a Fermi.

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Now I have a Zotac Geforce GTX 680 2Gb. I am tempted to buy another one, exactly the same and connect them with a SLI bridge. I am just thinking how much more productive the rig will become? Will it crunch 2 WU at the same time or 1 but twice as fast?
Is having a double SLI-ed GPU justified performance-wise??
Thank you.

Now I have a Zotac Geforce GTX 680 2Gb. I am tempted to buy another one, exactly the same and connect them with a SLI bridge. I am just thinking how much more productive the rig will become? Will it crunch 2 WU at the same time or 1 but twice as fast?
Is having a double SLI-ed GPU justified performance-wise??
Thank you.

Hello: Hello: First do not connect the SLI bridge.

Install the second card and nothing else, otherwise the two cards will not work.

Perform two tasks simultaneously.

According to the Windows driver that uses BOINC may not recognize the second card, you must modify the configuration file of Boinc, cc_config.xml, adding "<use_all_gpus> 1 </ use_all_gpus>".

In Linux (Ubuntu) no problem and recognizes the two cards directly. Greetings.

I have Windows7-64.
So if I connect two cards with SLI, it will not give me any growth in performance? One WU will be working same as before??
Only if the 2 cards are independent, then they will crunch 2 WUs simultaneously, correct??
If so that's a pity, because I was hoping to use the advantage of 2 SLI-ed cards in games... But that's minor.
I could not find cc_config.xml, I'll have to create it in Notepad? Is there an example of how it should look like?

Found this:
<cc_config>
<options>
<report_results_immediately> 1 </ report_results_immediately>
<use_all_gpus> 1 </ use_all_gpus>
</ options>
</ cc_config>

Is it correct?

Hello: That is correct can not increase the performance of a task with SLI, is that BOINC does not recognize external SLI, only internal card GTX590 or GTX690 type double.

Your cc_config.xml okay.

From my experience with the recent drivers you can have the bridge installed and SLI enabled and still crunch on GPUGrid just fine.


Yup just tried it, the tasks run the same, one on each card, same GPU utilization %, only the system is slightly laggy on occasion. But crunching fine.

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XtremeSystems.org - #1 Team in GPUGrid

Ok after a while Chrome and also Internet Explorer were VERY laggy when running 2 tasks while SLI is enabled. So you can definitely have the bridge installed but I would not recommend having SLI enabled while you are crunching. You can snooze BOINC and exit, enable SLI and play your game, and the disable SLI and then reopen BOINC if you want.

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XtremeSystems.org - #1 Team in GPUGrid

Hmm, good point, I think it will be possible to disable SLI in NVidia control panel. Also, if I decide to really load the GPUs with crunching only, I can switch the video output to the CPU built-in graphics, which is quite powerful they say. Thank everyone for the advice.

I could not find cc_config.xml, I'll have to create it in Notepad? Is there an example of how it should look like?

Here is a little guide on how to check and create the cc_config.xml on Win7, if you've installed the BOINC manager into the default location.

Did everything by the guide. That's what Boinc reported when I clicked "Read local pref file":

Missing end tag in cc_config.xml

Error in cc_config.xml options

Unrecognized tag in cc_config.xml: <report_results_immediately>

One WU is running, the 2nd is "Ready to start".
What else can I try?