diff --git a/Atari/gr_basics.asm b/Atari/gr_basics.asm
index 7b30739..1716a74 100644
--- a/Atari/gr_basics.asm
+++ b/Atari/gr_basics.asm
@@ -197,12 +197,6 @@ ClearPlot
     mva #1 color
 
 drawmountainsloop
-    ldy #0
-    lda (modify),y
-    cmp #screenheight
-    beq NoMountain
-    sta ydraw
-    sty ydraw+1
 .IF FASTER_GRAF_PROCS = 1
     ; calculate lower point in one screen byte
     lda xdraw
@@ -217,8 +211,15 @@ NotLower
     bpl @-
     sta temp2
     inc temp2	; this is our minimum
-    iny
 MinCalculated
+.ENDIF
+    ldy #0
+    lda (modify),y
+    cmp #screenheight
+    beq NoMountain
+    sta ydraw
+    sty ydraw+1
+.IF FASTER_GRAF_PROCS = 1
 ;    there was Drawline proc
     jsr plot.MakePlot
     ; after plot we have: (xbyte),y - addres of screen byte; X - index in bittable (number of bit)
diff --git a/C64/gr_basics.asm b/C64/gr_basics.asm
index 5750d8c..8a1c1eb 100644
--- a/C64/gr_basics.asm
+++ b/C64/gr_basics.asm
@@ -184,12 +184,6 @@ ClearPlot
     mva #1 color
 
 drawmountainsloop
-    ldy #0
-    lda (modify),y
-    cmp #screenheight
-    beq NoMountain
-    sta ydraw
-    sty ydraw+1
 .IF FASTER_GRAF_PROCS = 1
     ; calculate lower point in one screen byte
     lda xdraw
@@ -205,8 +199,15 @@ NotLower
     bpl @-
     sta temp2
     inc temp2	; this is our minimum
-    iny
 MinCalculated
+.ENDIF
+    ldy #0
+    lda (modify),y
+    cmp #screenheight
+    beq NoMountain
+    sta ydraw
+    sty ydraw+1
+.IF FASTER_GRAF_PROCS = 1
 ;    there was Drawline proc
     lda #screenheight
     sec
diff --git a/scorch.xex b/scorch.xex
index c2c56cc..eda21da 100644
Binary files a/scorch.xex and b/scorch.xex differ
diff --git a/scorchC64.prg b/scorchC64.prg
index 0f670e9..23e65d3 100644
Binary files a/scorchC64.prg and b/scorchC64.prg differ