diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBC_GB_PPU.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBC_GB_PPU.cs
index 1d741d2fb7..161cc6f198 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBC_GB_PPU.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBC_GB_PPU.cs
@@ -584,7 +584,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 				{
 					if (STAT.Bit(4))
 					{
-						if ((cycle >= 4) && (LY == 144))
+						if ((cycle >= 5) && (LY == 144))
 						{
 							VBL_INT = true;
 						}
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBC_PPU.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBC_PPU.cs
index 3fb9ac992e..8d1d65429d 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBC_PPU.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBC_PPU.cs
@@ -587,7 +587,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 				{
 					if (STAT.Bit(4))
 					{
-						if ((cycle >= 4) && (LY == 144))
+						if ((cycle >= (3 + 1 * LYC_offset)) && (LY == 144))
 						{
 							VBL_INT = true;
 						}