Hello,

On my device (NVIDIA's GeForce 9400 GT) I ran the following command:

Code :
clGetDeviceInfo(devices[i], CL_DEVICE_PREFERRED_VECTOR_WIDTH_FLOAT, 		
            sizeof(vec_width), &vec_width, NULL);

I got vec_width=1.
Does it make sense ?

I ran the following kernel and got correct results:

Code :
__kernel void matvec_mult(__global float4* matrix,
                          __global float4* vector,
                          __global float* result) {
 
   int i = get_global_id(0);
   result[i] = dot(matrix[i], vector[0]);
}

So it seems the NVIDIA device supports at least a vecotr of 4 floats.

I'm using AMD's SDK. Can this cause the problem ?

Thanks,
Zvika