It sounds like you are trying to call the ACML SGEMM from a C program. The likely cause of the error is a problem with the type of parameters you are using.
An example call from C should look like:
char transA = 'N';
char transB = 'N';
int m, int n, int k;
float alpha = 1.0;
float beta = 0.0;
sgemm (transA, transB, m, n, k, alpha, Adata, lda, Bdata, ldb, beta, Cdata, m);
You mentioned your graphics card.
ACML and MKL right now do not make use of the graphics card. I don't know how to do it with the ATI cards but cuda provide cublas.a which has sgemv() I would assume that the AMD GPU libararies have similar tools.