Looking to get started with GPU processing

tbret
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RE: I guess I'm doing

Quote:

I guess I'm doing alright? Does it mean I could or should decrease my utilization factor further?

As Zalster said, you really should take control of that fan and raise it. 60C is about as high as you want to go with a 750Ti.

You really can safely ignore the "danger" of doing multiple work units. Many of us have been doing two tasks at a time on a single 750Ti for months.

But, I'd turn the fan up. I think mine are operating in the mid-40C range. I'll check if you want me to.

John Reed
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Adjusting fan speed in

Adjusting fan speed in Ubuntu... a lovely three-hour tour.

I know how I did it, but one thing bugs me.

The catch is I'm trying to do everything without a monitor and in ssh. No dice. So, I plug in a monitor and created an xorg.conf with nvidia-xconfig(never done this before so I dont know what this file is for). Added Coolbits=4 and rebooted. My resolution was messed up, but I could adjust the fan speed with nvidia-settings. However, I lost my IP address. I removed everything in xorg.conf except for the NVIDIA stuff and rebooted. I had normal resolution and could adjust the fan speed, but still no IP address. Mucked around some more but didn't really change anything, rebooted again and got an IP address that time.

It's working. Set an arbitrary 80% speed and now I'm down to 53 C, and I can ssh. But I wish I knew why rebooting twice with an xorg.conf file messed with my networking, but a third or forth reboot did it...

Gary Roberts
Gary Roberts
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RE: The catch is I'm trying

Quote:
The catch is I'm trying to do everything without a monitor and in ssh.


While you are configuring the machine, just hook up the peripherals and do things the easy way. If you are using a half decent distro, your hardware will be correctly detected and xorg.conf will be correctly set up automatically during the installation process. So, have pity on the installer and make sure the screen you intend to use at any later stage is in place during the installation.

Even if you subsequently change monitors, a reboot should cause the new device to be detected and set up automatically. On the odd chance that things are wrong (eg resolution) there should be a nice GUI tool available to change those sorts of parameters without you having to know how to edit xorg.conf yourself. In this day and age it should be a relatively rare event for you to have to need to generate xorg.conf yourself. I certainly wouldn't let nvidia-xconfig do it because it is not distro specific. I would take the view that the distro maintainers are much more likely to know how to do it properly for their own particular distro. So, to use Coolbits options, I would just add them manually with a text editor, and leave all other options untouched.

Quote:
My resolution was messed up, but I could adjust the fan speed with nvidia-settings. However, I lost my IP address. I removed everything in xorg.conf except for the NVIDIA stuff and rebooted. I had normal resolution and could adjust the fan speed, but still no IP address. Mucked around some more but didn't really change anything, rebooted again and got an IP address that time.


The wrong resolution was most likely caused by nvidia-xconfig getting it wrong. The loss of IP address would be nothing to do with nvidia-xconfig. Most distros would have some sort of control center where you can easily renew the IP address without having to reboot. You need to work that out for your distro of choice. Spend some time looking for and using whatever GUI tools are available to do these various jobs quickly and easily. This is not Microsoft. Good tools are available and things aren't hidden away so the user can't find them. "If in doubt just reboot" is not usually needed around here :-).

Cheers,
Gary.

John Reed
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RE: While you are

Quote:
While you are configuring the machine, just hook up the peripherals and do things the easy way. If you are using a half decent distro, your hardware will be correctly detected and xorg.conf will be correctly set up automatically during the installation process. So, have pity on the installer and make sure the screen you intend to use at any later stage is in place during the installation.


Thanks for the great insights, Gary. One thing that puzzles me however, I did do the install with this same monitor connected originally. When I reconnected it to change the fan speed, I did not have an xorg.conf file. So when I read you need one to add Coolbits, I also read that you can create one with nvidia-xconfig. But why didn't I have one? Did I have an xorg.conf after the install but lost it somehow?

AgentB
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RE: RE: While you are

Quote:
Quote:
While you are configuring the machine, just hook up the peripherals and do things the easy way. If you are using a half decent distro, your hardware will be correctly detected and xorg.conf will be correctly set up automatically during the installation process. So, have pity on the installer and make sure the screen you intend to use at any later stage is in place during the installation.

Thanks for the great insights, Gary. One thing that puzzles me however, I did do the install with this same monitor connected originally. When I reconnected it to change the fan speed, I did not have an xorg.conf file. So when I read you need one to add Coolbits, I also read that you can create one with nvidia-xconfig. But why didn't I have one? Did I have an xorg.conf after the install
but lost it somehow?

You don't say what errors were displayed, i'd suggest several hours spent in
/var/log/Xorg.*.log (or wherever they are on your system)

The xorg.conf file can exist in many places, i'd also suggest

man xorg.conf
and
man nvidia-xconfig

to get a deeper understanding.

Gary Roberts
Gary Roberts
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RE: When I reconnected it

Quote:
When I reconnected it to change the fan speed, I did not have an xorg.conf file. So when I read you need one to add Coolbits, I also read that you can create one with nvidia-xconfig. But why didn't I have one? Did I have an xorg.conf after the install but lost it somehow?


X server configuration varies from distro to distro. The standard place for xorg.conf is /etc/X11/xorg.conf. Some distros have a directory, xorg.conf.d/ and various config files go in there. So you might find /etc/X11/xorg.conf.d/*.conf where *.conf are a series of config files, usually starting with a 2 digit number, with each file representing a section of the full xorg.conf. An example might be nn-monitor.conf. The 2 digit nn is used to ensure configs are processed numerically in a 'correct' order. Such a file would be used to override defaults and set special config options for a particular monitor.

Other distros (like ubuntu - I believe but don't know for sure) have done away with the xorg.conf file completely. Are you using ubuntu? The distro I use creates automatically the file /etc/X11/xorg.conf which can be manually edited to tweak Coolbits stuff.

For distros that have done away with xorg.conf completely, you can still create one (or sections for one - see above) if you need to. For example you could create a nn-devices.conf just for the Coolbits options for a particular device. The standard way to create X server configuration in a separate file is just to run (as root) the command

# Xorg :1 -configure

I believe this should create a basic xorg.conf file with the name xorg.conf.new in root's login directory (ie /root/xorg.conf.new) which you can then copy to /etc/X11/xorg.conf after adding any Coolbits options. You can check if any such file already exists and where it is located with the command

$ locate xorg.conf

Since my distro has an xorg.conf (it gets created automatically if it is missing), I've never had to worry too much about the details. I haven't used other distros so I don't have any real experience with what others do. The above comments are things I've read from time to time. You should consult the documentation for your distro or perhaps ask questions on their forums to get the best advice. On the odd occasion that I need to change the config (eg card swaps, monitor swaps, resolution changes), there is both a CLI and a GUI tool to do the job.

I have a whole range of both nvidia and AMD cards and all were properly detected and configured during the basic installation stage. I have manually added Coolbits options to nvidia cards in the past but don't use any at the moment. I believe 60C for a fully loaded graphics card is quite OK. I might start to worry if it got above 75C or so but not 60C. I've seen cards (AMD HD4850) operating without issue (no invalids or crashes) at 85-90C. Of course, once discovered, I've quickly fixed the problem - in that case the TIM (thermal interface material) had dried out and needed replacing. I still run those cards at Milkyway since they can't be used here at Einstein. The temps show around 80C at the moment. They're over 6 years old and have always run fairly warm.

My oldest nvidia cards are 550Tis. I've just checked one of those and it's running at 78C. It's been running fine like this for around 4 years. They get this warm because the room temperature is around 34C. It's a hot summer's day outside, even though summer doesn't officially start for another couple of days yet :-).

Cheers,
Gary.

lightning_anime
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Hello, While I have been

Hello,

While I have been doing GPU computing for many years, I am interested in stepping up my crunching performance. From the reading that I have done in this thread and many others it appears the GTX 750 TI has good performance/watt. I am interested in putting three into a computer that can provide PCIE2 x16/x8/x8. Three GTX 750Ti should allow me to up my crunching performance significantly. I am interested in this setup after looking at the top computers and seeing |MATMAN|'s quad GTX750Ti PC, which is rank 22 for RAC. This setup would appear to be very power efficient for the RAC versus the other systems at the top.

What I am concerned about is airflow to the 1st and 2nd cards. In the past I ran a pair of ASUS GTX650-E-2GD5 in a computer, but the primary card seemed to run on the warm side. The card never throttled and the temps never caused the fan to spin-up to high. However after about a year, I came home to find my computer offline. It ended up the primary GTX650 had died. Which I confirmed by trying the primary GTX650 in several computers and PCIE slots, but it was never recognized. The motherboard was fine as it recognized the second GTX650 with no trouble in the primary PCIE slot. My only thought is that with no empty slots between the two graphics cards the primary card died due to heat.

I have been looking at the Zotac GTX750TI which appear to be a 1.5 height card which might help the 1st and 2nd cards to get air and allow the cards to run on the cooler side. I have also looked at cards like the EVGA GTX750TI blower style, which appear to be a full 2 slots. With the EVGA cards taking up two slots it would seem the 1st and 2nd cards would be starved for air with no real gap between the cards resulting in the cards running on the hot side.

Does anyone have any thoughts on which card type might be better in a multigraphics card setup? What are your thoughts on Zotac Graphics cards? I have only used EVGA and Asus cards in the past.

Thanks for any help you can provide.

Robert

Zalster
Zalster
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Hello Robert, First 750Ti

Hello Robert,

First 750Ti are good cards, I've owned several over the past year.

Second, Matman is not running 4 750Tis. It just looks that way because of the way Boinc recognizes cards in a computer

He is actually running

the Intel GPU on his chip
GPU 0 is a Titan Black
GPU 1 is a GTX 750 Ti
GPU 2 is a GTX 750 Ti

Those are his 4 GPUs in that system.

Like you, I've only ever used EVGA cards, I like them. But you are right airflow thru the case is an issue. I resolved my issues with airflow by using small spacers between the GPU to allow for better air flow and putting several fans in the front and directly over the GPU pushing air over the cars to help keep them cool.

My 2 cents...

Zalster

Edit..

Robert were you looking at the single fan or dual fan cards?

woohoo
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running two might be easier

running two might be easier then running three, like maybe dual 960, or one 960 and one 750

lightning_anime
lightning_anime
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Hi Zalster, Thanks for the

Hi Zalster,

Thanks for the info on Matman's PC. Not sure why a Titan Black would be listed as two GTX750TI when the Titan Black only has one GPU on the card. I could understand maybe a Titan Z being reported as two graphics cards with its two gpus.

I also see tapir's computer ID: 4610346 at 39 on the Top computers list with what appears to be three GTX750 TI cards unless that is also being reported incorrectly.

For the EVGA GTX 750TI, I was looking at either the base model or the superclocked with a single fan as they do not require an additional power plug and have listed power consumption of 60 watts. The FTW model with dual fans requires a power plug and has a power consumption of 85 watts. The extra 25 watts to get only 13MHZ over the superclocked and drive a second fan does not seem worth it. The other concern with the dual fan FTW is that it would dump more heat back into the case versus ejecting it out the back of the case. In addition I notice that the base model and superclocked are often on sale sometimes for ~$100-110, whereas the FTW even on sale typically goes for $30-40 more. The cost and small performance gain do not justify the extra cost to me.

My goal is to get close to the best performance I can get for the dollar and power consumption. My plan would be to use my current i7-920 and place the three GTX750ti in it, moving the GTX650 to my i3-530 without a graphics card. Yes, I know an i7-920 is not exactly a power efficient CPU by today's standards with its 130W TDP, but the system is paid for.

The three graphics cards should cost $300-$340 and should provide an estimated additional 150-200K RAC with some tuning of the system. This looks like the best bang for the dollar and power consumption.

I am heat dissipation limited and noise limited. I do not have a spare room to put the computer, so it has to be as quiet as possible and generate the least amount of heat for the performance.

Have you ever used a Refurbished card from EVGA? Reading the reviews I see mixed reviews on the refurbished cards.

Robert

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