diff --git a/core/hw/naomi/gdcartridge.cpp b/core/hw/naomi/gdcartridge.cpp
index c57f6ae96..74ca9b91f 100644
--- a/core/hw/naomi/gdcartridge.cpp
+++ b/core/hw/naomi/gdcartridge.cpp
@@ -456,7 +456,11 @@ void GDCartridge::read_gdrom(Disc *gdrom, u32 sector, u8* dst)
 
 void GDCartridge::device_start()
 {
-	dimm_data = NULL;
+	if (dimm_data != NULL)
+	{
+		free(dimm_data);
+		dimm_data = NULL;
+	}
 	dimm_data_size = 0;
 
 	char name[128];
diff --git a/core/hw/naomi/gdcartridge.h b/core/hw/naomi/gdcartridge.h
index 7408c4883..121239581 100644
--- a/core/hw/naomi/gdcartridge.h
+++ b/core/hw/naomi/gdcartridge.h
@@ -21,6 +21,13 @@ public:
 	GDCartridge(u32 size) : NaomiCartridge(size)
 	{
 		gdrom_name = NULL;
+		dimm_data = NULL;
+		dimm_data_size = 0;
+		dimm_cur_address = 0;
+	}
+	~GDCartridge()
+	{
+		free(dimm_data);
 	}
 	virtual void Init() override
 	{