I have a an AMD Athlon 64 x2 3800+2 Manchester running Win7 x32.

Is that cpu sufficient to drive 2 x GTX 670's?

It will only run GPUGrid tasks

How much GPU performance, if any, is lost if this CPU won't drive it at its max?

I'm considering an 850 watt power supply and not planning on OC'ing.

Thanks

Ken Florian

Need to know the motherboard to be specific.

BUT I can say this. You will lose A LOT. Not only are the PCIe lanes going to be 1.x, but the CPU @ 2.0GHz, and the slow RAM will also hurt.

850W is also overkill.

Post full system specs and you may get a better answer.

Hi 5pot,

I have access to two each of the following. I'd been hoping I could coerce them into service with an upgraded ps and gpu...but it sounds like these are both too far gone to be of much use...certainly not the $500 to $600 per box to bring the gpu and ps to current standards.

Curious to know your further thoughts.


• AMD Phenom Quad Core 9500
• XFX Geforce 8200, 1066
• WinXP x64
• 8G ram

• AMD Athlon 64 x2 3800+2
• Gigabyte GA-K8N Pro-SLI
• Win7 x32
• 2G ram

[edit - Win7 x64 to Winxp x64]

How about 1 gpu per box...still not worth it because of the diminished performance?

The desire to put in two gpus comes only from wanting to contribute as much as possible.

Maybe better to build a real cruncher, over time.

Overclock your CPUs. You should get 40% out of them without much effort. The increased performance will help to keep your GPUs busy.

Even with stock CPU coolers, the AMDs should have lots of available performance.

Let us know how it goes.


____________
Thx - Paul

Note: Please don't use driver version 295 or 296! Recommended versions are 266 - 285.

Hi Paul,

I will update this post as I learn more.

One thing I do not know how to interpret...the Athlon is running 1 550TI on GPUGrid. Nothing else, except default windows services, is running.

swan_sync = 0
boinc 7.0.25

The GPUGrid WU shows 0.451 cpus + 1 nvidia.

What is the correct interpretation of "0.451"? Does it mean that the core is working as hard as GPU needs it to, or would that number be higher or lower, with a more capable CPU?

Thank you for taking the time to help.

Ken Floria

The GA-K8N Pro-SLI is based on the standard nForce4 SLI chipset, which means it has two 8x PCI-E slots, although one slot can be configured to run with the full 16 lanes if you don't have SLI. Unfortunately, the two high-speed PCI-E slots are only separated by one of the two 1x PCI-E slots, and you also have to manually flip an SO-DIMM card when you want to enable or disable SLI - most motherboards now allow you to do this in the BIOS.

Ken:

That is a great question. I usually see something like 0.51. I don't know what this really means.

Does anyone else have a clue about this information? What does that 0.41 or 0.51 mean?

thanks
____________
Thx - Paul

Note: Please don't use driver version 295 or 296! Recommended versions are 266 - 285.

After several days of refreshing my memory on things like actual electricity costs and the cost of building a temporarily modern crunching machine, I am leaning toward saying thanks but no thanks to inheriting this set of 5 to 7 year old machines. The emerging plan is to build one machine each year for the next couple of years to dedicate to grid computing-based research.

I'm going to keep my one gpugrid machine running for now...might as well...but might be able to bump my contribution in a significant way in the coming weeks.

Ken

I continue to refine my thinking...hence the question:

Assuming ram, psu, and mobo are up to the task...what is the fastest CPU required to optimize 2 GTX 670's or 680's in one physical machine?

For instance, does a 3930K enable the GTX to deliver more than a 3770?

One of my systems is a Q6600 @ 3GHz that keeps a GTX 590 at 98% utilization on Windows XP. On a second system, the a Q6600 @ 3.2GHZ is feeding 2 GTX 570s and they stay busy.

Your question is great in that some amount of CPU is required to "feed" the GPU data but you will likely find the requirements are far less than expected.

A i7-920 @ 3.7GHz keeps 2 GTX 580s working 24 x7. You need not go crazy on the CPU. Just get the 670 running with some CPU and get it attached to the project. We need the help!
____________
Thx - Paul

Note: Please don't use driver version 295 or 296! Recommended versions are 266 - 285.

skgiven and Paul,

Thanks. You are being a tremendous help as I think about how to get involved in a bigger way.

For curiosity, I moved the 550TI from the Athlon / Gigabye (which had been set on non-sli mode in the so-dimm) to an Intel DP35DP / Core2Duo 8200. The GPUGrid task now reads 0.364 CPU's + 1 NVDIA GPU.

The Athlon typically showed a GPU load of about 90%...the 8200 looks to be running it at about 94%. These are very informal observations...not recorded.

I just found skgiven's post about Win7 running about 11% slower than XP...very interesting and relevant to my project.

Ken

My Windows XP system typically keeps the GPUs at 97% utilization. My Windows 7 systems are usually at 89%. This is with the same processor and same type of GPU.

Windows XP and Linux clearly provide the greatest utilization while Windows 7 appears to be the most common OS.

____________
Thx - Paul

Note: Please don't use driver version 295 or 296! Recommended versions are 266 - 285.

My Windows XP system typically keeps the GPUs at 97% utilization. My Windows 7 systems are usually at 89%. This is with the same processor and same type of GPU.

Windows XP and Linux clearly provide the greatest utilization while Windows 7 appears to be the most common OS.

Ken, for an older technology, why not use older GPU's?

I have a similar CPU, Computer ID: 124381, an Intel Core2 Duo E6320 @ 1.86GHz, backed up by 1GB RAM, with a GTX 275 stuffed inside it. This PC is using Windows XP Professional x86 Edition, Service Pack 3, (05.01.2600.00). Current RAC is about 110,000 as of 6/6/2012. One core is dedicated for for the GPU, Swan_Sync, Variable Value: 0. When it's second core is in use, off busy running SETI, the performance of the GTX 275, on GPUGRID does not suffer. It will have the same performance whether the CPU usage is at 50% or at 100%. When this card was used in a more modern PC, Core i3 530, Windows 7, 4GB RAM, it's RAC was a good 10,000 to 12,000 lower, than when used with this PC's E6320, proving once again, that the operating system, XP, not the CPU as much, is more superior to Windows 7, performance when used in GPUGRID.

To answer your question, I think it can handle 2 of these ancient GTX's at the same time, by utilizing both of it's cores, but I can only speculate that these could be the newer Kepler's. The PCIe 1.0 architecture of my Motherboard, will hold back the performance of newer GPU's, but it seems to be compatible with the ancient 200 Series GTX's. From searching through the RAC of the top 200 computers on GPUGRID, I think it could handle a Fermi as well.

BTW, this PC was built from left over parts, cost was nil. Rather than keep it retired in the closet, I figured, why not donate it, use it, for Scientific projects. It might have half the RAC of a modern PC, but it is contributing to this project.

Folks,

This is all great thinking and helpful input. The analysis I'm meandering through is the best performance for dollar spent, all-inclusive over the useable lifetime of the equipment. "All-inclusive" means electricity costs for 6 years and purchase(s) of new equipment, if any. I want to support GPUGrid and probably WCG.

I am an old hand at building my own pc's but I am very new to understanding gpu / cpu crunching optimized for research. Between this thread and this thread http://www.gpugrid.net/forum_thread.php?id=2998
it is possibly looking like building a single box for a hybrid gpu/cpu crunching is not the most cost effective solution.

For instance, reserving 1 core of a 3930 for 1 GTX-6x0 seems 'wasteful' if a GTX-6x0 could be driving to its limit by, say, a "modern" i3 cpu.

One angle I have been considering is a 3930 cpu with 2 GTX-6x0's in it for GPUGrid and a 2 cpu's for WCG.

I am all for using old gear in whatever way possible wut when I look at the annual electricity costs of, say the Phenom at 24x7, compared to the 3820 and the amount of 'research' each could deliver, the cost to keep the Phenom running compared to buying new seems silly.

No conclusions...just musings and thanks to all.

Ken

You make some great points and the cost of electricity can be a factor in some parts of the world. In Tennessee, we pay about $0.08 per KWH. If the entire computers uses 1 KWH per hour, that is 168 KWHs a week or 732 KWH a month. That is about $58 per month per computer. It will take a while to save enough for a new rig. In addition, Intel and AMD will continue to innovate and find more efficient ways to complete more instructions per second so slap something together and get started.

You will learn a lot about your builds in the process. I never knew how many hotspots my systems had until I started overclocking GTX 570s and 580s. These things can generate some heat. Learn on the older stuff so you can apply your new skills on your new purchases. Don't learn with a $1,000 GTX 690. Ouch!

You need not dedicate a processor to each GPU. Just get a rig running and play around with the settings. I use Swan_Sync but I continue to let BOINC have 100% of the processors. This means that Rosetta at Home continues to run 1 process per processor. My GPUs are seldom starved for data.

We look forward to whatever you decide to do to contribute to the project!

____________
Thx - Paul

Note: Please don't use driver version 295 or 296! Recommended versions are 266 - 285.

Thanks Paul!

My one 550TI is running now in on an intel 8200.... no plan to turn it off...just deciding where to go next. "Negotiations" with my minister of finance went astonishingly well. We were due to upgrade our contributions to the common good...here is a fine place to do so.

Ken

Could you provide some tips on your negotiation techniques? One of the issues I have is the fact that all "parts" purchases need to be approved. Something about how we spend too much money on my hobby, bla bla bla.

I try to buy almost everything on craigslist or ebay to keep the costs down and I still have a few thousand invested in hardware. My electric bill, well, it is always a topic of discussion.

Glad to hear your negotiations went well and we look forward to a multi GTX 690 rig in your future!
____________
Thx - Paul

Note: Please don't use driver version 295 or 296! Recommended versions are 266 - 285.

Could you provide some tips on your negotiation techniques?

Ken:

Do you have a blog because I would love to follow it. You are a funny guy.

I have one open slot in one of my computers and I will likely save up some cash to buy a GTX 590.

My first order of business is to get my existing 590 to run for more than 24 hours.

Keep crunching!
____________
Thx - Paul

Note: Please don't use driver version 295 or 296! Recommended versions are 266 - 285.

I use a sneaky approach to get round my other half. What see doesn't see she doesn't know about. I schedule parts deliveries to arrive whilst she is out at work - I work a rotating shift pattern so orders are placed timed to arrive when I'm off and she is at work. My cases stay the same, but it's whats inside changes.

Fiendish? Of course...... but then so is she..... her growing collection of shoes is testament to that..... she is a budding Imelda Marcos!!!

Going to be sticking with my old Phenoms II's for a while, switching to Bulldozer would lose performance for my systems, so my next upgrades will probably be GPU and most probably it will be a 570 or 670 for my second hex core rig.

Do you have a blog because I would love to follow it. You are a funny guy.

I schedule parts deliveries to arrive whilst she is out at work.

Great posts everyone in regards to the Minister of Finance. Found them very funny and true.......

kflorian:

in case you're looking for a good case as well. This is a Corsair Graphite 600T, and I have found this one to be excellent for GPU crunching, since you can add intake fans that suck in air from the outside and it goes directly to the GPUs. There are a total of 4 slots on the side, and each one can use a 120mm fan. I prefer radiator type fans that have curved blades for a higher static pressure. This allows them to suck more air thru those holes. Currently using this method to cool a 680 and a 670. There is also one 200mm fan on top sucking hot air out, as well as another 200mm fan at the front of the case that sucks air in as well. The knob at the top of the case is a fan controller, and can come in handy if noise is an issue.

For what it's worth, currently my system:

3820@4.3
Gigabyte 670 stock speeds
EVGA 680 stock
ASUS Sabertooth
120 GB SSD
H70 CORE w/ a push/pull config
Seasonic X Gold? 750W PSU

This setup currently uses 550W at wall. I do have one regret, and that is not getting the H100. Temps are not an issue AT ALL, but I still wish I would have forked over the extra $30. I am also going to be switching the 670 to another rig when my 2nd 680 arrives. Those things are hard to find....

5pot,

thanks for the config specs. I like that case, too. I've been eyeing the Antec P280. What are your typical ambient temperatures in the room in which the machine is located?

Ken

Ken:

The GTX 590 is fine. The entire rig needs to be adjusted. A few changes tonight and it is running again at 662MHz. We will see how many hours we get this time. This XP system has been around for a while. Keeping 2 GPUs running is almost twice the work of keeping 1 running.

GTX 580s are down to $200 on ebay. I am starting to think my 570s need to be upgraded :-)
____________
Thx - Paul

Note: Please don't use driver version 295 or 296! Recommended versions are 266 - 285.

@kflorian:

Currently my ambient temps are 24C. I recently got another 680, so both are now in this rig crunching away for Einstein@Home. Waiting for GPUgrid to open up. The top GPU is at 60C w/ 67% fan and the bottom one is at 57C w/ 64% fan. Both hover around 87% utilization. I must have misread my Watts before, because currently my APC UPS (universal power supply) is currently stating roughly 450W. HIGHLY SUGGEST getting one to protect your investment. If you do decide to go 3 670/680 I would say get a 850W PSU for optimum efficiency.

Here is a pic of the three fans in a L shape attached to the case:


As well as the two cards and the system inside: