diff --git a/src/swrenderer/drawers/r_draw_span32.h b/src/swrenderer/drawers/r_draw_span32.h
index 02a616d46..dcd43312f 100644
--- a/src/swrenderer/drawers/r_draw_span32.h
+++ b/src/swrenderer/drawers/r_draw_span32.h
@@ -329,7 +329,7 @@ namespace swrenderer
 				float Lyz2 = light_y; // L.y*L.y + L.z*L.z
 				float Lx = light_x - viewpos_x;
 				float dist2 = Lyz2 + Lx * Lx;
-				float rcp_dist = _mm_cvtss_f32(_mm_rsqrt_ss(_mm_set_ss(dist2)));
+				float rcp_dist = 1.f/sqrt(dist2);
 				float dist = dist2 * rcp_dist;
 				float distance_attenuation = 256.0f - MIN(dist * light_radius, 256.0f);
 
diff --git a/src/swrenderer/drawers/r_draw_wall32.h b/src/swrenderer/drawers/r_draw_wall32.h
index d3b4a7cc4..b39379528 100644
--- a/src/swrenderer/drawers/r_draw_wall32.h
+++ b/src/swrenderer/drawers/r_draw_wall32.h
@@ -249,7 +249,7 @@ namespace swrenderer
 				float Lxy2 = light_x; // L.x*L.x + L.y*L.y
 				float Lz = light_z - viewpos_z;
 				float dist2 = Lxy2 + Lz * Lz;
-				float rcp_dist = _mm_cvtss_f32(_mm_rsqrt_ss(_mm_set_ss(dist2)));
+				float rcp_dist = 1.f/sqrt(dist2);
 				float dist = dist2 * rcp_dist;
 				float distance_attenuation = 256.0f - MIN(dist * light_radius, 256.0f);