diff --git a/common/g45/hw-gfx-gma-power_and_clocks.adb b/common/g45/hw-gfx-gma-power_and_clocks.adb
index e082a6d..3c73dcc 100644
--- a/common/g45/hw-gfx-gma-power_and_clocks.adb
+++ b/common/g45/hw-gfx-gma-power_and_clocks.adb
@@ -102,7 +102,7 @@
    is
       use type HW.Word16;
 
-      Tmp_Clk : Int64 := 0;
+      Tmp_Clk : Int64;
 
       VCO : Int64;
       Divisors : Div_Array;
@@ -110,23 +110,21 @@
       GCFGC : Word16;
       CDClk_Sel : Natural range 0 .. 7;
    begin
-      if PCI_Usable then
-         Get_VCO (VCO, Divisors);
-         PCI_Read16 (GCFGC, 16#f0#);
-         if Config.GMCH_GM965 then
-            -- Linux i965gm_get_cdclk: cdclk_sel = ((tmp >> 8) & 0x1f) - 1
-            if (Shift_Right (GCFGC, 8) and 16#1f#) in 1 .. 3 then
-               CDClk_Sel := Natural (Shift_Right (GCFGC, 8) and 16#1f#) - 1;
-            else
-               CDClk_Sel := Div_Array'Last;
-            end if;
-         elsif Config.Has_GMCH_Mobile_VCO then
-            CDClk_Sel := Natural (Shift_Right (GCFGC, 12) and 1);
+      Get_VCO (VCO, Divisors);
+      PCI_Read16 (GCFGC, 16#f0#);
+      if Config.GMCH_GM965 then
+         -- Linux i965gm_get_cdclk: cdclk_sel = ((tmp >> 8) & 0x1f) - 1
+         if (Shift_Right (GCFGC, 8) and 16#1f#) in 1 .. 3 then
+            CDClk_Sel := Natural (Shift_Right (GCFGC, 8) and 16#1f#) - 1;
          else
-            CDClk_Sel := Natural (Shift_Right (GCFGC, 4) and 7);
+            CDClk_Sel := Div_Array'Last;
          end if;
-         Tmp_Clk := VCO / Divisors (CDClk_Sel);
+      elsif Config.Has_GMCH_Mobile_VCO then
+         CDClk_Sel := Natural (Shift_Right (GCFGC, 12) and 1);
+      else
+         CDClk_Sel := Natural (Shift_Right (GCFGC, 4) and 7);
       end if;
+      Tmp_Clk := VCO / Divisors (CDClk_Sel);
 
       if Tmp_Clk in Config.CDClk_Range then
          CDClk := Tmp_Clk;
diff --git a/common/hw-gfx-gma-registers.adb b/common/hw-gfx-gma-registers.adb
index 41aae0a..d54949b 100644
--- a/common/hw-gfx-gma-registers.adb
+++ b/common/hw-gfx-gma-registers.adb
@@ -353,14 +353,6 @@
       pragma Debug (Verbose, Debug.Put_Line (Registers_Index'Image (Register)));
    end Read;
 
-   procedure Read_AUD_VID_DID (Value : out Word32)
-   is
-   begin
-      Regs.Read
-        (Value,
-         Registers_Range (Config.AUD_VID_DID_Offset / Register_Width));
-   end Read_AUD_VID_DID;
-
    ----------------------------------------------------------------------------
 
    -- Read a specific register to post a previous write
diff --git a/common/hw-gfx-gma-registers.ads b/common/hw-gfx-gma-registers.ads
index 1245c9f..df9f11f 100644
--- a/common/hw-gfx-gma-registers.ads
+++ b/common/hw-gfx-gma-registers.ads
@@ -2311,13 +2311,6 @@
       Pre     => True,
       Post    => True;
 
-   procedure Read_AUD_VID_DID (Value : out Word32)
-   with
-      Global  => (In_Out => Register_State),
-      Depends => ((Value, Register_State) => Register_State),
-      Pre     => True,
-      Post    => True;
-
    procedure Write
       (Register : Registers_Index;
        Value    : Word32;
diff --git a/common/hw-gfx-gma.adb b/common/hw-gfx-gma.adb
index fc8005f..449f7b3 100644
--- a/common/hw-gfx-gma.adb
+++ b/common/hw-gfx-gma.adb
@@ -38,7 +38,6 @@
    with Refined_State =>
      (State =>
         (Config.Variable,
-         PCI_Usable,
          Dev.Address_State,
          Registers.Address_State,
          PCode.Mailbox_Ready,
@@ -495,8 +494,7 @@
            (Dev.PCI_State, Port_IO.State,
             Registers.Register_State, Registers.GTT_State),
          Output =>
-           (PCI_Usable,
-            Config.Variable,
+           (Config.Variable,
             Dev.Address_State,
             Registers.Address_State,
             PCode.Mailbox_Ready,
@@ -514,32 +512,6 @@
 
       Now : constant Time.T := Time.Now;
 
-      procedure Check_Platform (Success : out Boolean)
-      is
-         Audio_VID_DID : Word32;
-      begin
-         if Config.Gen_I945 or Config.GMCH_GM965 then
-            -- i945 and GM965 have no integrated audio DID to verify.
-            Success := True;
-            return;
-         end if;
-         Registers.Read_AUD_VID_DID (Audio_VID_DID);
-         Success :=
-           ((Config.Gen_Broxton        and Audio_VID_DID = 16#8086_280a#) or
-            (Config.CPU_Kabylake       and Audio_VID_DID = 16#8086_280b#) or
-            (Config.CPU_Skylake        and Audio_VID_DID = 16#8086_2809#) or
-            (Config.CPU_Broadwell      and Audio_VID_DID = 16#8086_2808#) or
-            (Config.CPU_Haswell        and Audio_VID_DID = 16#8086_2807#) or
-            ((Config.CPU_Ivybridge or
-              Config.CPU_Sandybridge)  and (Audio_VID_DID = 16#8086_2806# or
-                                            Audio_VID_DID = 16#8086_2805#)) or
-            (Config.CPU_Ironlake       and Audio_VID_DID = 16#0000_0000#) or
-            (Config.Gen_G45            and (Audio_VID_DID = 16#8086_2801# or
-                                            Audio_VID_DID = 16#8086_2802# or
-                                            Audio_VID_DID = 16#8086_2803#)) or
-            (Config.CPU_Tigerlake      and (Audio_VID_DID = 16#8086_2812#)));
-      end Check_Platform;
-
       procedure Check_Platform_PCI (Success : out Boolean)
       is
          use type HW.Word16;
@@ -556,7 +528,6 @@
 
       pragma Debug (Debug.Set_Register_Write_Delay (Write_Delay));
 
-      PCI_Usable := False;
       Linear_FB_Base := 0;
       PCode.Mailbox_Ready := False;
       Wait_For_HPD := HPD_Type'(others => False);
@@ -575,10 +546,15 @@
       PLLs.Initialize;
 
       Dev.Initialize (Success);
+      pragma Debug (not Success, Debug.Put_Line ("ERROR: Couldn't initialize PCI dev."));
 
       if Success then
          Check_Platform_PCI (Success);
-         if Success then
+         pragma Debug (not Success, Debug.Put_Line ("ERROR: Incompatible GPU."));
+      end if;
+
+      if Success then
+         if HW.Config.Dynamic_MMIO then
             if Config.Has_I945_GTT_BAR then
                -- i945: MMIO is on BAR0, GTT is on separate BAR3
                Dev.Map (PCI_MMIO_Base, PCI.Res0);
@@ -589,30 +565,22 @@
                Dev.Map
                  (PCI_GTT_Base, PCI.Res0, Offset => Config.MMIO_GTT_Offset);
             end if;
+
             if PCI_MMIO_Base /= 0 and PCI_GTT_Base /= 0 then
                Registers.Set_Register_Base (PCI_MMIO_Base, PCI_GTT_Base);
-               PCI_Usable := True;
             else
-               pragma Debug (Debug.Put_Line
-                 ("ERROR: Couldn't map resource0."));
-               Success := Config.Default_MMIO_Base_Set;
+               pragma Debug (Debug.Put_Line ("ERROR: Couldn't map resource0."));
+               Success := False;
             end if;
-         end if;
-      else
-         pragma Debug (Debug.Put_Line
-           ("WARNING: Couldn't initialize PCI dev."));
-         Success := Config.Default_MMIO_Base_Set;
-
-         if Success then
-            Check_Platform (Success);
+         else
+            Success := Config.Default_MMIO_Base_Set;
+            pragma Debug (not Success, Debug.Put_Line ("ERROR: MMIO base not set."));
          end if;
       end if;
 
       Panel.Static_Init;   -- early for flow analysis
 
       if not Success then
-         pragma Debug (Debug.Put_Line ("ERROR: Incompatible CPU or PCH."));
-
          Initialized := False;
          return;
       end if;
diff --git a/common/hw-gfx-gma.ads b/common/hw-gfx-gma.ads
index 76424d6..c33c513 100644
--- a/common/hw-gfx-gma.ads
+++ b/common/hw-gfx-gma.ads
@@ -276,11 +276,10 @@
 
 private
 
-   PCI_Usable : Boolean with Part_Of => State;
    use type HW.PCI.Index;
    procedure PCI_Read16 (Value : out Word16; Offset : HW.PCI.Index)
    with
-      Pre => PCI_Usable and Offset mod 2 = 0;
+      Pre => Offset mod 2 = 0;
 
    ----------------------------------------------------------------------------
 
diff --git a/common/i945/hw-gfx-gma-power_and_clocks.adb b/common/i945/hw-gfx-gma-power_and_clocks.adb
index 23d5476..2f6404a 100644
--- a/common/i945/hw-gfx-gma-power_and_clocks.adb
+++ b/common/i945/hw-gfx-gma-power_and_clocks.adb
@@ -49,28 +49,19 @@
       GC_DISPLAY_CLOCK_320_MHZ     : constant Word16 := 4 * 2 ** 4;
 
       GCFGC : Word16;
-      Tmp_Clk : Frequency_Type := 200_000_000;
    begin
       if Config.GMCH_I945GM then
-         if PCI_Usable then
-            PCI_Read16 (GCFGC, 16#f0#);
-            if (GCFGC and GC_LOW_FREQUENCY_ENABLE) /= 0 then
-               Tmp_Clk := 133_333_333;
-            elsif (GCFGC and GC_DISPLAY_CLOCK_MASK) = GC_DISPLAY_CLOCK_320_MHZ then
-               Tmp_Clk := 320_000_000;
-            else
-               Tmp_Clk := 200_000_000;
-            end if;
+         PCI_Read16 (GCFGC, 16#f0#);
+         if (GCFGC and GC_LOW_FREQUENCY_ENABLE) /= 0 then
+            CDClk := 133_333_333;
+         elsif (GCFGC and GC_DISPLAY_CLOCK_MASK) = GC_DISPLAY_CLOCK_320_MHZ then
+            CDClk := 320_000_000;
+         else
+            CDClk := 200_000_000;
          end if;
       else
          -- i945G desktop: fixed 400 MHz
-         Tmp_Clk := 400_000_000;
-      end if;
-
-      if Tmp_Clk in Config.CDClk_Range then
-         CDClk := Tmp_Clk;
-      else
-         CDClk := 200_000_000;
+         CDClk := 400_000_000;
       end if;
    end Get_CDClk;