Put some numbers already, please :-) I would like to see also P55.

Concurrent bandwidth is when data is sent simultaneously to and from graphics card. Current graphics cards do not support this feature (data is not sent in the same time) so this number is similar to htod and dtoh, but Fermi supports bidirectional pcie transfers.

Yes, I would like to see number to see to what to upgrade.

Result is on console (it is console application), open it in cmd.exe.  Or you can redirect also output to the file.

My complete test

concBandwidthTest.exe 0
Device 0 took 1061.812012 ms
Average HtoD bandwidth in MB/s: 6027.432285
Device 0 took 1239.142334 ms
Average DtoH bandwidth in MB/s: 5164.862683
Device 0 took 2440.794189 ms
Average bidirectional bandwidth in MB/s: 5244.194720
 
concBandwidthTest.exe 0 1
Device 0 took 2050.442627 ms
Device 1 took 2154.234375 ms
Average HtoD bandwidth in MB/s: 6092.170368
Device 0 took 1965.233643 ms
Device 1 took 2061.018555 ms
Average DtoH bandwidth in MB/s: 6361.870977
Device 0 took 4153.288086 ms
Device 1 took 4147.257813 ms
Average bidirectional bandwidth in MB/s: 6168.272262
 
concBandwidthTest.exe 0 1 2
Device 0 took 3085.135986 ms
Device 1 took 2445.103760 ms
Device 2 took 2988.076904 ms
Average HtoD bandwidth in MB/s: 6833.784497
Device 0 took 3006.738037 ms
Device 1 took 3071.671875 ms
Device 2 took 2026.984863 ms
Average DtoH bandwidth in MB/s: 7369.507469
Device 0 took 6013.095215 ms
Device 1 took 6113.502930 ms
Device 2 took 3942.925781 ms
Average bidirectional bandwidth in MB/s: 7468.733690

This is with my GTX295:

Device 0 took 2476.597900 ms
Device 1 took 2471.752441 ms
Average HtoD bandwidth in MB/s: 5173.446255
Device 0 took 2376.772705 ms
Device 1 took 2376.782715 ms
Average DtoH bandwidth in MB/s: 5385.442629
Device 0 took 3953.334717 ms
Device 1 took 3928.907471 ms
Average bidirectional bandwidth in MB/s: 6495.676041

tried running this thing but a window flashes then poof nothing. 

slayer_27

I ran it. Is there some sort of output file? The cmd closes before I could even try to copy the numbers.

You can also run it in the command prompt and type in:
 
concBandwidthTest.exe [flags] => output.txt
 
The "=>" tells it to output the results to the place you indicate instead of on the screen.
 

slayer_27

ok, got ya. I was running it with a flagged shortcut.

 
You could make a batch file with the following text in it:
 

call "concBandwidthTest.exe" 0 => Results.txt

 
Subsitute the 0 for the proper number of GPUs in your system.
 
Then save the batch file (*.bat) in the same location as the concBandwidthTest.exe application.  Testing would then be as simple as double clicking the batch file and viewing the results located in results.txt.
 
And if you wanted to get really fancy, you would place this into the batch file:
 

 @echo off 
     cls 
     echo -------------------------------------------------------------------- 
     echo A test is being run to check the PCI-E bandwidth of your video card. 
     echo After the test is finished, you can view the results of the test 
     echo located in the results.txt file within the same directory. 
     echo -------------------------------------------------------------------- 
     echo PCI-E Bandwidth test: > Header0.txt 
     echo ---------------------------------------------------- > Spacer1.txt 
     echo The test 1 is running . . . 
     call "concBandwidthTest.exe" 0 => Result1.txt 
     echo The results of test 1: > Header1.txt 
     echo The test 2 is running . . . 
     call "concBandwidthTest.exe" 0 => Result2.txt 
     echo The results of test 2: > Header2.txt 
     echo The test 3 is running . . . 
     call "concBandwidthTest.exe" 0 => Result3.txt 
     echo The results of test 3: > Header3.txt 
     copy Header0.txt + Spacer1.txt + Header1.txt + Result1.txt + Spacer1.txt + Header2.txt + Result2.txt + Spacer1.txt + Header3.txt + Result3.txt Results.txt 
     del Result1.txt /q 
     del Result2.txt /q 
     del Result3.txt /q 
     del Header0.txt /q 
     del Header1.txt /q 
     del Header2.txt /q 
     del Header3.txt /q 
     del Spacer1.txt /q 

 
This would result in a file called Results.txt containing:
 
PCI-E Bandwidth test:
----------------------------------------------------
The results of test 1:
Device 0 took 3060.420654 ms
Average HtoD bandwidth in MB/s: 2091.215791
Device 0 took 4040.131836 ms
Average DtoH bandwidth in MB/s: 1584.106722
Device 0 took 7093.834473 ms
Average bidirectional bandwidth in MB/s: 1804.383800
----------------------------------------------------
The results of test 2:
Device 0 took 3073.665527 ms
Average HtoD bandwidth in MB/s: 2082.204437
Device 0 took 3993.211182 ms
Average DtoH bandwidth in MB/s: 1602.720144
Device 0 took 7010.831055 ms
Average bidirectional bandwidth in MB/s: 1825.746463
----------------------------------------------------
The results of test 3:
Device 0 took 3049.834717 ms
Average HtoD bandwidth in MB/s: 2098.474375
Device 0 took 3990.640137 ms
Average DtoH bandwidth in MB/s: 1603.752727
Device 0 took 6974.415527 ms
Average bidirectional bandwidth in MB/s: 1835.279236


Here is with my GPU (8800M GTS) overclocked 550 / 1375 / 880:
 
Device 0 took 3093.272461 ms
Average HtoD bandwidth in MB/s: 2069.006232
Device 0 took 4277.136719 ms
Average DtoH bandwidth in MB/s: 1496.328133
Device 0 took 7481.359375 ms
Average bidirectional bandwidth in MB/s: 1710.919013
 
Here is with my GPU at default clocks (500 / 1250 / 799):
 
Device 0 took 3090.146973 ms
Average HtoD bandwidth in MB/s: 2071.098901
Device 0 took 4258.783203 ms
Average DtoH bandwidth in MB/s: 1502.776661
Device 0 took 7366.389648 ms
Average bidirectional bandwidth in MB/s: 1737.621903
 
The difference?  Not really much of any.  So what does this test actually test?  Does it test the ability of the video card to saturate the PCI-E bus or does it reflect the performance of the video card in any way or does it simply show how well your PCI-E bus is able to provide information to the video card as needed?
 
In other words, why are my numbers so much lower than everyone elses?  Is it simply because my video card is underpowered?  Or is it because my motherboard isn't able to efficiently communicate with the video card?  Or is it some sort of combination of the two?

ty_ger07
So what does this test actually test?  Does it test the ability of the video card to saturate the PCI-E bus or does it reflect the performance of the video card in any way or does it simply show how well your PCI-E bus is able to provide information to the video card as needed?

 
Title of thread is PCI-E bandwidth test, it measures how quickly data is transfered through PCIE. Graphics card is used because it is simple to do test with cuda.
 
Original idea (see nvidia forums) is also to observe how bandwidth is influenced with many concurrent transfers (more graphics cards).
 
If you use more graphics cards PCIE will be more saturated to its limit.
 
You can check with this also if everything is running ok (bios settings ...)
 
PS:
Usage is concBandwidthTest <numbers divided by space>
 
numbers are ids of graphics cards
e.g.
concBandwidthTest 0 1 2
tests 3 graphics cards running transfers concurrently
 
concBandwidthTest 0 2
tests gfx card 0 and 2 running transfers concurrently
 
 
 

TrekCZ

Title of thread is PCI-E bandwidth test, it measures how quickly data is transfered through PCIE. Graphics card is used because it is simple to do test with cuda.
 
Original idea (see nvidia forums) is also to observe how bandwidth is influenced with many concurrent transfers (more graphics cards).
 
If you use more graphics cards PCIE will be more saturated to its limit.
 
You can check with this also if everything is running ok (bios settings ...) 

 
So you are saying that the reason why my results are low is because my laptop is apparently just not any good at sending data along the PCI-E bus for whatever reason?  Your saying that the performance of the card has nothing to do with the results?
 
Gateway P-6860fx
Core 2 Duo T9300 2.5GHz dual core / 800MHz FSB
 
Laptop PCI-E power saving kicking into affect?

TrekCZ

Video memory is faster in magnitudes in relation to pcie bandwidth.

So you are basically sending data to the video card's memory and from the video card's memory and testing how fast it is sent and what sort of latency in incurred.
 
How much data are you sending?
 
Does this data originate from system memory?  Or is the data sent from the video card's memory sent to system memory at any point?  The reason I ask is becuase I am wondering if the speed and latency of the system memory is a factor.
 
I really have no clue of the mechanics behind your test, but I would assume that the CPU would have some role in controlling the process and therefore would matter to the results.  I see that when I do this test, my CPU load jumps up to and stays at 50%.  So, I am assuming that the test is only using one of two cores of my CPU and possibly that is part of the reason for my low results.
 
EDIT:  After watching the test run a few times, I am seeing that it is using a varying amount of system memory and reaches a peak of 300MB of system memory during the test.  So I am assuming that the data for the test is created and sent to the video card and then sent back to and temporarily stored in system memory.
 
This assumption being the case, the test would also test the efficiencies of the board's memory controller and memory latency and speed.
 
Being that I am testing on a laptop with only a 200MHz FSB (800MHz effective), am running memory at a bus speed of 333MHz (667MHz effective), and the test is only utilizing one of the two cores of my CPU, there appears to be many things working against me.

GPU-Z says my bus is PCI-E 2.0 x16 @ 16x.  But CPU-Z says that my bus is at x1 with a max link width of x16.  This has been an ongoing puzzle for me.  So I am really not sure what speed my bus is at any one time. 
 
I notice that if I boot my laptop up when it is unplugged from the wall, GPU-Z says that it is running at PCI-E 2.0 x16 @ x1.  So I realize there is some sort of power saving feature kicking in, but am left assuming that when the PCI-E bus is being utilized, it will jump to x16 in any event.
 
"multi or single core should not have influence"
 
That doesn't really calm my concern because I am seeing one core reaching 100% load and the other one not being stressed.  Doesn't that show a sign that the program could need more CPU processing power if it were allowed to get it?
 
"PPS: Of  course with notebook you cannot be CUDA king, because notebooks are limited in many ways "
 
I realize that.  But I would like to use your utility to better understand my system and what performance bottlenecks are present.

Here are the results from my PC:
 
PCI-E Bandwidth test:
----------------------------------------------------
The results of test 1:
Device 0 took 2382.700439 ms
Device 1 took 2428.679688 ms
Device 2 took 1234.408447 ms
Average HtoD bandwidth in MB/s: 10505.874249
Device 0 took 2244.881592 ms
Device 1 took 2173.757568 ms
Device 2 took 2577.528564 ms
Average DtoH bandwidth in MB/s: 8278.139114
Device 0 took 4962.038574 ms
Device 1 took 4881.741211 ms
Device 2 took 3374.004150 ms
Average bidirectional bandwidth in MB/s: 8995.312205
----------------------------------------------------
The results of test 2:
Device 0 took 2412.077393 ms
Device 1 took 2458.301514 ms
Device 2 took 1239.455444 ms
Average HtoD bandwidth in MB/s: 10420.296000
Device 0 took 2179.921387 ms
Device 1 took 2182.174072 ms
Device 2 took 2599.595459 ms
Average DtoH bandwidth in MB/s: 8330.662143
Device 0 took 4931.510254 ms
Device 1 took 4871.004883 ms
Device 2 took 3367.029053 ms
Average bidirectional bandwidth in MB/s: 9024.919295
----------------------------------------------------
The results of test 3:
Device 0 took 2417.023682 ms
Device 1 took 2418.754150 ms
Device 2 took 1325.867432 ms
Average HtoD bandwidth in MB/s: 10120.903572
Device 0 took 2193.666260 ms
Device 1 took 2135.444092 ms
Device 2 took 2597.337646 ms
Average DtoH bandwidth in MB/s: 8378.586581
Device 0 took 4826.146484 ms
Device 1 took 4857.119629 ms
Device 2 took 3248.195801 ms
Average bidirectional bandwidth in MB/s: 9228.175402
 
 
Quite a contrast.
 
Core i7 965 @ 4GHz.  6GB 1,600MHz RAM.  3x GTX 285.

Yes concBandwidthTest.exe 0 1 tests both cards from GTX295.

These 10 gigs numbers for x58 are nice, it would be interesting to see it for P55.