diff --git a/Core/MMC5.h b/Core/MMC5.h
index b40d954c..dacecf7f 100644
--- a/Core/MMC5.h
+++ b/Core/MMC5.h
@@ -316,7 +316,8 @@ protected:
 
 		_fillModeNametable = new uint8_t[0x400];
 		_emptyNametable = new uint8_t[0x400];
-		memset(_emptyNametable, 0, 0x400);
+		InitializeRam(_emptyNametable, 0x400);
+		InitializeRam(_fillModeNametable, 0x400);
 
 		//"Expansion RAM ($5C00-$5FFF, read/write)"
 		SetCpuMemoryMapping(0x5C00, 0x5FFF, 0, PrgMemoryType::WorkRam);
diff --git a/Core/PPU.cpp b/Core/PPU.cpp
index 922e7041..3f50695a 100644
--- a/Core/PPU.cpp
+++ b/Core/PPU.cpp
@@ -76,7 +76,7 @@ void PPU::Reset()
 	_cyclesNeeded = 0.0;
 
 	memset(_hasSprite, 0, sizeof(_hasSprite));
-	memset(_spriteTiles, 0, sizeof(SpriteInfo));
+	memset(_spriteTiles, 0, sizeof(_spriteTiles));
 	_spriteCount = 0;
 	_secondaryOAMAddr = 0;
 	_sprite0Visible = false;