diff --git a/src/det.irp.f b/src/det.irp.f
index 0982d07..85494f2 100644
--- a/src/det.irp.f
+++ b/src/det.irp.f
@@ -1114,6 +1114,9 @@ end
  endif
  !DIR$ FORCEINLINE
  call bitstring_to_list ( psi_det_alpha(1,det_i), mo_list_alpha_curr, l, N_int )
+ if (l /= elec_alpha_num) then
+   stop 'error in number of alpha electrons'
+ endif
 
 END_PROVIDER
 
@@ -1132,8 +1135,12 @@ END_PROVIDER
  else
    mo_list_beta_prev = 0
  endif
+
  !DIR$ FORCEINLINE
  call bitstring_to_list ( psi_det_beta(1,det_j), mo_list_beta_curr, l, N_int )
+ if (l /= elec_beta_num) then
+   stop 'error in number of beta electrons'
+ endif
 END_PROVIDER
 
  BEGIN_PROVIDER [ double precision, det_alpha_value_curr ]
diff --git a/src/mo.irp.f b/src/mo.irp.f
index eb300af..4b9bba7 100644
--- a/src/mo.irp.f
+++ b/src/mo.irp.f
@@ -701,13 +701,13 @@ subroutine sparse_full_mv(A,LDA,                                     &
   
   ! LDC and LDA have to be factors of simd_sp
   
-  IRP_IF NO_PREFETCH
-  IRP_ELSE
-    call MM_PREFETCH (A(j,indices(1)),3)
-    call MM_PREFETCH (A(j,indices(2)),3)
-    call MM_PREFETCH (A(j,indices(3)),3)
-    call MM_PREFETCH (A(j,indices(4)),3)
-  IRP_ENDIF
+!  IRP_IF NO_PREFETCH
+!  IRP_ELSE
+!    call MM_PREFETCH (A(1,indices(1)),3)
+!    call MM_PREFETCH (A(1,indices(2)),3)
+!    call MM_PREFETCH (A(1,indices(3)),3)
+!    call MM_PREFETCH (A(1,indices(4)),3)
+!  IRP_ENDIF
 
   !DIR$ SIMD
   do j=1,LDC
@@ -757,13 +757,13 @@ subroutine sparse_full_mv(A,LDA,                                     &
       !DIR$ VECTOR ALIGNED
       !DIR$ SIMD FIRSTPRIVATE(d11,d21,d31,d41)
       do j=1,$IRP_ALIGN/4
-        IRP_IF NO_PREFETCH
-        IRP_ELSE
-          call MM_PREFETCH (A(j+k,indices(kao+4)),3)
-          call MM_PREFETCH (A(j+k,indices(kao+5)),3)
-          call MM_PREFETCH (A(j+k,indices(kao+6)),3)
-          call MM_PREFETCH (A(j+k,indices(kao+7)),3)
-        IRP_ENDIF
+!        IRP_IF NO_PREFETCH
+!        IRP_ELSE
+!          call MM_PREFETCH (A(j+k,indices(kao+4)),3)
+!          call MM_PREFETCH (A(j+k,indices(kao+5)),3)
+!          call MM_PREFETCH (A(j+k,indices(kao+6)),3)
+!          call MM_PREFETCH (A(j+k,indices(kao+7)),3)
+!        IRP_ENDIF
         C1(j+k) = C1(j+k) + A(j+k,k_vec(1))*d11 + A(j+k,k_vec(2))*d21&
             +   A(j+k,k_vec(3))*d31 + A(j+k,k_vec(4))*d41
       enddo