This is a newbie’s question.
I have two GeForce 8800 GTX cards on a motherboard.
After booting the system, I get this message from devicequiery;
#############################################
device 0: “GeForce 8800 GTX”
Revision number: 1.0
Total amount of global memory: 804585472 bytes
Total amount of constant memory: 65536 bytes
Total amount of shared memory per block: 16384 bytes
Total number of registers available per block: 8192
Warp size: 32
Maximum number of threads per block: 512
Maximum sizes of each dimension of a block: 512 x 512 x 64
Maximum sizes of each dimension of a grid: 65535 x 65535 x 1
Maximum memory pitch: 262144 bytes
Texture alignment: 256 bytes
Clock rate: 1188000 kilohertz
Time for cudaSetDevice is 0.005 in ms
device 1: “GeForce 8800 GTX”
Revision number: 1.0
Total amount of global memory: 805044224 bytes
Total amount of constant memory: 65536 bytes
Total amount of shared memory per block: 16384 bytes
Total number of registers available per block: 8192
Warp size: 32
Maximum number of threads per block: 512
Maximum sizes of each dimension of a block: 512 x 512 x 64
Maximum sizes of each dimension of a grid: 65535 x 65535 x 1
Maximum memory pitch: 262144 bytes
Texture alignment: 256 bytes
Clock rate: 1350000 kilohertz
##########################################
It says that device 0 has a clock rate 1.18 Ghz while the device 1 has
1.35 Ghz <img src=‘http://hqnveipbwb20/public/style_emoticons/<#EMO_DIR#>/crying.gif’ class=‘bbc_emoticon’ alt=‘:’(’ /> . But after startx-ing, I get the clock rate of the device 0 swithed to
1.35 Ghz. I wonder whether this is common or specific to my machine.
The device driver is a version of x86_64 Kernel Module 169.09 and
the os kernel version is 2.6.23.12-52.fc7 #1 SMP.
And there is another question. After booting, the super user has to run any
cuda application in order for other users to see the muti-gpu cards.
Before that the user can see only the first cards.
Many thanks.
Juhan