diff --git a/lib/gpu/lal_beck.cu b/lib/gpu/lal_beck.cu
index a2a15e4d21..12f1314c52 100644
--- a/lib/gpu/lal_beck.cu
+++ b/lib/gpu/lal_beck.cu
@@ -88,7 +88,7 @@ __kernel void k_beck(const __global numtyp4 *restrict x_,
         numtyp alphaij = beck1[mtype].y;
         numtyp betaij = beck1[mtype].z;
         numtyp term1 = aaij*aaij + rsq;
-        numtyp term2 = pow(term1,(numtyp)-5.0);
+        numtyp term2 = (numtyp)1.0/(term1*term1*term1*term1*term1); // ucl_powr(term1,(numtyp)-5.0);
         numtyp term3 = (numtyp)21.672 + (numtyp)30.0*aaij*aaij + (numtyp)6.0*rsq;
         numtyp term4 = alphaij + r5*betaij;
         numtyp term5 = alphaij + (numtyp)6.0*r5*betaij;
@@ -102,7 +102,7 @@ __kernel void k_beck(const __global numtyp4 *restrict x_,
         f.z+=delz*force;
 
         if (EVFLAG && eflag) {
-          numtyp term6 = pow(term1,(numtyp)-3);
+          numtyp term6 = (numtyp)1.0/(term1*term1*term1); //ucl_powr(term1,(numtyp)-3);
           numtyp term1inv = ucl_recip(term1);
           numtyp e = beck2[mtype].x*ucl_exp((numtyp)-1.0*r*term4);
           e -= beck2[mtype].y*term6*((numtyp)1.0+((numtyp)2.709+(numtyp)3.0*aaij*aaij)*term1inv);
@@ -193,7 +193,7 @@ __kernel void k_beck_fast(const __global numtyp4 *restrict x_,
         numtyp alphaij = beck1[mtype].y;
         numtyp betaij = beck1[mtype].z;
         numtyp term1 = aaij*aaij + rsq;
-        numtyp term2 = pow(term1,(numtyp)-5.0);
+        numtyp term2 = (numtyp)1.0/(term1*term1*term1*term1*term1); //ucl_powr(term1,(numtyp)-5.0);
         numtyp term3 = (numtyp)21.672 + (numtyp)30.0*aaij*aaij + (numtyp)6.0*rsq;
         numtyp term4 = alphaij + r5*betaij;
         numtyp term5 = alphaij + (numtyp)6.0*r5*betaij;
@@ -207,7 +207,7 @@ __kernel void k_beck_fast(const __global numtyp4 *restrict x_,
         f.z+=delz*force;
 
         if (EVFLAG && eflag) {
-          numtyp term6 = pow(term1,(numtyp)-3);
+          numtyp term6 = (numtyp)1.0/(term1*term1*term1); //ucl_powr(term1,(numtyp)-3);
           numtyp term1inv = ucl_recip(term1);
           numtyp e = beck2[mtype].x*ucl_exp((numtyp)-1.0*r*term4);
           e -= beck2[mtype].y*term6*((numtyp)1.0+((numtyp)2.709+(numtyp)3.0*aaij*aaij)*term1inv);
diff --git a/lib/gpu/lal_colloid.cu b/lib/gpu/lal_colloid.cu
index 8a20f0c400..f59215e882 100644
--- a/lib/gpu/lal_colloid.cu
+++ b/lib/gpu/lal_colloid.cu
@@ -123,10 +123,10 @@ __kernel void k_colloid(const __global numtyp4 *restrict x_,
           K[6] = K[2]-r;
           K[7] = ucl_recip(K[3]*K[4]);
           K[8] = ucl_recip(K[5]*K[6]);
-          g[0] = ucl_powr(K[3],(numtyp)-7.0);
-          g[1] = -ucl_powr(-K[4],(numtyp)-7.0);
-          g[2] = ucl_powr(K[5],(numtyp)-7.0);
-          g[3] = -ucl_powr(-K[6],(numtyp)-7.0);
+          g[0] = (numtyp)1.0/(K[3]*K[3]*K[3]*K[3]*K[3]*K[3]*K[3]);  // ucl_powr(K[3],(numtyp)-7.0);
+          g[1] = (numtyp)1.0/(K[4]*K[4]*K[4]*K[4]*K[4]*K[4]*K[4]);  //-ucl_powr(-K[4],(numtyp)-7.0);
+          g[2] = (numtyp)1.0/(K[5]*K[5]*K[5]*K[5]*K[5]*K[5]*K[5]);  // ucl_powr(K[5],(numtyp)-7.0);
+          g[3] = (numtyp)1.0/(K[6]*K[6]*K[6]*K[6]*K[6]*K[6]*K[6]);  //-ucl_powr(-K[6],(numtyp)-7.0);
           h[0] = ((K[3]+(numtyp)5.0*K[1])*K[3]+(numtyp)30.0*K[0])*g[0];
           h[1] = ((K[4]+(numtyp)5.0*K[1])*K[4]+(numtyp)30.0*K[0])*g[1];
           h[2] = ((K[5]+(numtyp)5.0*K[2])*K[5]-(numtyp)30.0*K[0])*g[2];
@@ -290,10 +290,10 @@ __kernel void k_colloid_fast(const __global numtyp4 *restrict x_,
           K[6] = K[2]-r;
           K[7] = ucl_recip(K[3]*K[4]);
           K[8] = ucl_recip(K[5]*K[6]);
-          g[0] = ucl_powr(K[3],(numtyp)-7.0);
-          g[1] = -ucl_powr(-K[4],(numtyp)-7.0);
-          g[2] = ucl_powr(K[5],(numtyp)-7.0);
-          g[3] = -ucl_powr(-K[6],(numtyp)-7.0);
+          g[0] = (numtyp)1.0/(K[3]*K[3]*K[3]*K[3]*K[3]*K[3]*K[3]);  // ucl_powr(K[3],(numtyp)-7.0);
+          g[1] = (numtyp)1.0/(K[4]*K[4]*K[4]*K[4]*K[4]*K[4]*K[4]);  //-ucl_powr(-K[4],(numtyp)-7.0);
+          g[2] = (numtyp)1.0/(K[5]*K[5]*K[5]*K[5]*K[5]*K[5]*K[5]);  // ucl_powr(K[5],(numtyp)-7.0);
+          g[3] = (numtyp)1.0/(K[6]*K[6]*K[6]*K[6]*K[6]*K[6]*K[6]);  //-ucl_powr(-K[6],(numtyp)-7.0);
           h[0] = ((K[3]+(numtyp)5.0*K[1])*K[3]+(numtyp)30.0*K[0])*g[0];
           h[1] = ((K[4]+(numtyp)5.0*K[1])*K[4]+(numtyp)30.0*K[0])*g[1];
           h[2] = ((K[5]+(numtyp)5.0*K[2])*K[5]-(numtyp)30.0*K[0])*g[2];