As I said in my earlier post I did try 3 but it did not work.
My K9A2 can in theory take 4 PCIE cards, but the system struggled with two GT240s, never mind four. At the time I did not have four cards to play with, but I might give it a go sometime.
I have however had 2 GPU cards and another non-GPU card just underneath the lower GPU, and a GPU sandwiched between 2 other cards in a tight midi case.
The problem with three or more is likely to be the exhaust air being brought back around and over the cards, especially the middle card(s). This would occur when the case fans are pushing too much air over the cards and the cards cannot expel all that air, so this warm air is brought back over the cards.
I alleviated this by reversing the airflow on a side case fan (turning it around, so that it blows air out from the GPUs), after installing a Big front case fan. I also found that leaving back plates off helps the air flow hugely. When I had my power greedy HD450 sandwiched between a sound card and a SATA RAID card in a midi case, I had to put a large fan blowing in from the front, and remove the back plates just to get it stable. The case had no side fan, and just a standard front fan was not enough to run the card stably. When I left the door off the temps plummeted, but it was too noisy so I took the back blanking plates off (a happy medium).

Tried to put 4 GT240 cards into my K9A12 Motherboard.
System boots, Boinc Loads but only sees 2 cards. GPU-Z can see all 4 cards as can EVGA Precision and the system, just not Boinc!

Tried latest drivers and Boinc Beta.
Edited cc_config to use all GPUs.

Still only sees 2 of the 4 cards!

Anyone?

15/04/2010 21:05:28 Starting BOINC client version 6.10.45 for windows_x86_64
15/04/2010 21:05:28 Config: report completed tasks immediately
15/04/2010 21:05:28 Config: use all coprocessors
15/04/2010 21:05:28 log flags: file_xfer, sched_ops, task
15/04/2010 21:05:28 Libraries: libcurl/7.19.7 OpenSSL/0.9.8l zlib/1.2.3
15/04/2010 21:05:28 Data directory: C:\ProgramData\BOINC
15/04/2010 21:05:28 Running under account X
15/04/2010 21:05:28 Processor: 4 AuthenticAMD AMD Phenom(tm) II X4 940 Processor [Family 16 Model 4 Stepping 2]
15/04/2010 21:05:28 Processor: 512.00 KB cache
15/04/2010 21:05:28 Processor features: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 htt pni cx16 syscall nx lm svm sse4a osvw ibs skinit wdt page1gb rdtscp 3dnowext 3dnow
15/04/2010 21:05:28 OS: Microsoft Windows Vista: Ultimate x64 Edition, Service Pack 1, (06.00.6001.00)
15/04/2010 21:05:28 Memory: 4.00 GB physical, 8.21 GB virtual
15/04/2010 21:05:28 Disk: 931.51 GB total, 700.11 GB free
15/04/2010 21:05:28 Local time is UTC +1 hours
15/04/2010 21:05:28 NVIDIA GPU 0: GeForce GT 240 (driver version 19745, CUDA version 3000, compute capability 1.2, 475MB, 257 GFLOPS peak)
15/04/2010 21:05:28 NVIDIA GPU 1: GeForce GT 240 (driver version 19745, CUDA version 3000, compute capability 1.2, 475MB, 257 GFLOPS peak)

15/04/2010 21:12:16 Re-reading cc_config.xml
15/04/2010 21:12:16 Re-read config file
15/04/2010 21:12:16 Config: report completed tasks immediately
15/04/2010 21:12:16 Config: use all coprocessors
15/04/2010 21:12:16 log flags: file_xfer, sched_ops, task

<cc_config>
<options>
<report_results_immediately>1</report_results_immediately>
<ncpus>0</ncpus>
<use_all_gpus>1</use_all_gpus>
</options>
</cc_config>

Thanks,

Removed 1 card, leaving 3 but Boinc only sees 2. The system sees 3 as does GPUZ and EVGA Precision and NVidia control panel.

As it was doing nothing I removed the 3rd card as well.

Pity, 4 GT240 cards would do the same work as a GTX295.

Any ideas and I can put them back in.

Anyone?

Have you tried putting a dummy load on two cards. It's all I can think of, sorry.

---

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I don't really know what you mean, dummy load?
Two cards presently work, but when I add a third or fourth they are not seen by Boinc.
Thanks,

I don't really know what you mean, dummy load?

You need to either attach them to monitors or use a dummy plug. Some KVMs also work. If they're not attached to something that looks remotely like a monitor they won't crunch WUs. Seems like a strange requirement, but true.

I will have another play about with it. Fortunately I have 2 KVM's to try. I dont have a dummy VGA/terminator, though I might be able to make one.
Reminds me of having to set up a dummy network port or bus networking.
Odd that the 2nd card works without any dummy connector.

Tried the KVM switches (both), but no joy.
The computer (device manager) can see all 4 cards and that they have the same driver. GPUZ can see them as can NVidia Control Panel, but Boinc is blind.

Tried the KVM switches (both), but no joy.
The computer (device manager) can see all 4 cards and that they have the same driver. GPUZ can see them as can NVidia Control Panel, but Boinc is blind.

When you right click on the desktop and look at the display are they all shown as active?

BOINC will not see them if they are not "active"... not only do you need the dummy or KVM, but need to make sure windows "extends" the desktop to all 4 displays. If you don't like the mouse disappearing (I just learned this trick) move the second window up so that only the corner is touching display 1... (or down) ...

When I had installed one secondary GPU I had this same problem, I could "see" the card, windows said it was working, so did the display panels and tools ... but BOINC is far more picky in the sense that ALL the ducks have to be in line before you can use the card.

Oh, and if they are all not identical you have to set the switch in cc config to use all GPUs or DA's smart code will lock some of them out ...

Thanks Paul, I forgot about extending the monitors after I wired up the KVM.
Boinc is now able to see 3 of the 4 cards; an improvement.

I use Vista, so for anyone else with this problem that has Vista/Win7,
Right Click on the desktop, Personalize, Display Settings, then extend your monitors to the other cards.

I have 7 cards listed here! (Device Manager correctly shows 4 GT240's.
In Display Settings there are,
Four, (Default Monitor) on NVIDIA GeForce GT 240,
and three, Generic non plug and play Monitor on NVIDIA GeForce GT 240

So, to get the fourth card working...

Ok, did you update cc config?

<use_all_gpus>1</use_all_gpus>

IIRC to get this flag to work you have to stop and restart BOINC...

What does BOINC show in the log for the GPU messages?

I uninstalled the drivers, restarted and reinstalled the drivers, restarted again, and then looked at the monitor extentions. Initially I could see all four cards in the list but when I extended the monitor one of the listed devices vanished. I think this suggests that one of my connections is not working, so I probably need to get a different video cable or get a dummy VGA plug.

I did restart Boinc again.

20/04/2010 11:48:51 Starting BOINC client version 6.10.45 for windows_x86_64
20/04/2010 11:48:51 Config: report completed tasks immediately
20/04/2010 11:48:51 Config: use all coprocessors
20/04/2010 11:48:51 log flags: file_xfer, sched_ops, task
20/04/2010 11:48:51 Libraries: libcurl/7.19.7 OpenSSL/0.9.8l zlib/1.2.3
20/04/2010 11:48:51 Data directory: C:\ProgramData\BOINC
20/04/2010 11:48:51 Running under account X
20/04/2010 11:48:51 Processor: 4 AuthenticAMD AMD Phenom(tm) II X4 940 Processor [Family 16 Model 4 Stepping 2]
20/04/2010 11:48:51 Processor: 512.00 KB cache
20/04/2010 11:48:51 Processor features: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 htt pni cx16 syscall nx lm svm sse4a osvw ibs skinit wdt page1gb rdtscp 3dnowext 3dnow
20/04/2010 11:48:51 OS: Microsoft Windows Vista: Ultimate x64 Edition, Service Pack 1, (06.00.6001.00)
20/04/2010 11:48:51 Memory: 4.00 GB physical, 8.17 GB virtual
20/04/2010 11:48:51 Disk: 931.51 GB total, 677.85 GB free
20/04/2010 11:48:51 Local time is UTC +1 hours
20/04/2010 11:48:51 NVIDIA GPU 0: GeForce GT 240 (driver version 19621, CUDA version 3000, compute capability 1.2, 512MB, 257 GFLOPS peak)
20/04/2010 11:48:51 NVIDIA GPU 1: GeForce GT 240 (driver version 19621, CUDA version 3000, compute capability 1.2, 512MB, 257 GFLOPS peak)
20/04/2010 11:48:51 NVIDIA GPU 2: GeForce GT 240 (driver version 19621, CUDA version 3000, compute capability 1.2, 512MB, 257 GFLOPS peak)


20/04/2010 13:27:12 Re-reading cc_config.xml
20/04/2010 13:27:12 Re-read config file
20/04/2010 13:27:12 Config: report completed tasks immediately
20/04/2010 13:27:12 Config: use all coprocessors


Thanks,

All you really need is 3 each 75 Ohm resistors per dummy cnx. You can make a dummy plug out of the DVI to VGA connector included with the video cards. There are articles on the net on the pin out. For each resistor, bend one of the leads down so both come out on the same side, clip them off even to start, find the depth of the connector and re-clip so the resistor is just above the connector when inserted.

Insert the resistor so that the body is on the "top"/wide part of the connector because that is the "hot" side, the middle pins are ground ...

Insert plugs, restart, and with luck the last one comes alive ...

I have to admit I have not tried the 4 GPU configs yet, mostly because I don't have a 4 GPU MB (yet) ... I hope in a month or so to be there ... but not yet ... :(

Finally, another cable brought Success!

20/04/2010 16:45:05 Starting BOINC client version 6.10.45 for windows_x86_64
20/04/2010 16:45:05 Config: report completed tasks immediately
20/04/2010 16:45:05 Config: use all coprocessors
20/04/2010 16:45:05 log flags: file_xfer, sched_ops, task
20/04/2010 16:45:05 Libraries: libcurl/7.19.7 OpenSSL/0.9.8l zlib/1.2.3
20/04/2010 16:45:05 Data directory: C:\ProgramData\BOINC
20/04/2010 16:45:05 Running under account X
20/04/2010 16:45:05 Processor: 4 AuthenticAMD AMD Phenom(tm) II X4 940 Processor [Family 16 Model 4 Stepping 2]
20/04/2010 16:45:05 Processor: 512.00 KB cache
20/04/2010 16:45:05 Processor features: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 htt pni cx16 syscall nx lm svm sse4a osvw ibs skinit wdt page1gb rdtscp 3dnowext 3dnow
20/04/2010 16:45:05 OS: Microsoft Windows Vista: Ultimate x64 Edition, Service Pack 1, (06.00.6001.00)
20/04/2010 16:45:05 Memory: 4.00 GB physical, 8.17 GB virtual
20/04/2010 16:45:05 Disk: 931.51 GB total, 677.68 GB free
20/04/2010 16:45:05 Local time is UTC +1 hours
20/04/2010 16:45:05 NVIDIA GPU 0: GeForce GT 240 (driver version 19621, CUDA version 3000, compute capability 1.2, 512MB, 281 GFLOPS peak)
20/04/2010 16:45:05 NVIDIA GPU 1: GeForce GT 240 (driver version 19621, CUDA version 3000, compute capability 1.2, 512MB, 281 GFLOPS peak)
20/04/2010 16:45:05 NVIDIA GPU 2: GeForce GT 240 (driver version 19621, CUDA version 3000, compute capability 1.2, 512MB, 281 GFLOPS peak)
20/04/2010 16:45:05 NVIDIA GPU 3: GeForce GT 240 (driver version 19621, CUDA version 3000, compute capability 1.2, 512MB, 281 GFLOPS peak)

Hardly superclocked (from 550MHz to 600MHz, with linked shaders and modest GDDR increases, 1800MHz), but I think it's fair to say the GT 240 has now been tried ;)

Thanks guys,

I suppose you can crank up the shaders much more than the core and GPU-Grid reacts well to shader clock :)

MrS

---

Scanning for our furry friends since Jan 2002

Thanks for the tip.
I will leave them as is for today, and have a go at upping the shaders tomorrow, after I pass my milestone :)
Although the case door is off, temps are between 54 and 64 deg C, so I should have a bit of leeway yet. The door also has a fan, in a very nice place and I can add another fan to the front of the Antec, nice and low, just opposite the GPUs.
On single card systems and dual card systems I can usually get slightly over 600MHz for these cores with the shaders tied; about 615MHz or 620MHz (though some can reach 640MHz) so if the shaders clock well then perhaps they will go past 1550MHz with the core kept at 600MHz?

I was actually considering changing that system (not the case), no chance of that now!

I wouldn't be surprised if your shaders hit 1.7 GHz :)

MrS

---

Scanning for our furry friends since Jan 2002

For now I am keeping the shaders at a slightly more modest 1.6GHz on the system with the four GTX240 cards.

I have other systems to test on, but when I tried a DDR3 Gigabyte GT240 I could not hit 1.7 without an almost immediate failure. Mind you the GPU on that card is at 640MHz and the Shaders now seem stable at 1.65. Not bad considering the NVidia ref. rates are 550MHz and 1340MHz.

The real test is to run the cards without any task failures.

- Typo, should read GT 240 (no X).

The 4 cards ran overnight without error :)
GPU 600MHz, Shaders 1600MHz.