diff --git a/core/hw/naomi/gdcartridge.cpp b/core/hw/naomi/gdcartridge.cpp
index 3f5b96f59..cdd00354f 100644
--- a/core/hw/naomi/gdcartridge.cpp
+++ b/core/hw/naomi/gdcartridge.cpp
@@ -502,26 +502,17 @@ void GDCartridge::device_start(LoadProgress *progress, std::vector<u8> *digest)
 		catch (const FlycastException& e)
 		{
 			WARN_LOG(NAOMI, "Opening chd failed: %s", e.what());
-			try {
-				gdrom = std::unique_ptr<Disc>(OpenDisc(gdrom_path + ".gdi", digest));
-			}
-			catch (const FlycastException& e)
+			if (gdrom_parent_name != nullptr)
 			{
-				if (gdrom_parent_name != nullptr)
-				{
-					std::string gdrom_parent_path = hostfs::storage().getSubPath(parent, std::string(gdrom_parent_name) + "/" + gdrom_name);
-					try {
-						gdrom = std::unique_ptr<Disc>(OpenDisc(gdrom_parent_path + ".chd", digest));
-					} catch (const FlycastException& e) {
-						WARN_LOG(NAOMI, "Opening parent chd failed: %s", e.what());
-						try {
-							gdrom = std::unique_ptr<Disc>(OpenDisc(gdrom_parent_path + ".gdi", digest));
-						} catch (const FlycastException& e) {}
-					}
+				std::string gdrom_parent_path = hostfs::storage().getSubPath(parent, std::string(gdrom_parent_name) + "/" + gdrom_name);
+				try {
+					gdrom = std::unique_ptr<Disc>(OpenDisc(gdrom_parent_path + ".chd", digest));
+				} catch (const FlycastException& e) {
+					WARN_LOG(NAOMI, "Opening parent chd failed: %s", e.what());
 				}
-				if (gdrom == nullptr)
-					throw NaomiCartException("Naomi GDROM: Cannot open " + gdrom_path + ".chd or " + gdrom_path + ".gdi");
 			}
+			if (gdrom == nullptr)
+				throw NaomiCartException("Naomi GDROM: Cannot open " + gdrom_path + ".chd");
 		}
 
 		// primary volume descriptor
diff --git a/core/hw/naomi/naomi_cart.cpp b/core/hw/naomi/naomi_cart.cpp
index 4b70e1899..ae0757297 100644
--- a/core/hw/naomi/naomi_cart.cpp
+++ b/core/hw/naomi/naomi_cart.cpp
@@ -81,12 +81,7 @@ static bool loadBios(const char *filename, Archive *child_archive, Archive *pare
 
 	for (int romid = 0; bios->blobs[romid].filename != nullptr; romid++)
 	{
-		if (region == -1)
-		{
-			region = bios->blobs[romid].region;
-			config::Region.override(region);
-		}
-		else if (bios->blobs[romid].region != (u32)region)
+		if (region != -1 && bios->blobs[romid].region != (u32)region)
 			continue;
 
 		std::unique_ptr<ArchiveFile> file;
@@ -119,6 +114,8 @@ static bool loadBios(const char *filename, Archive *child_archive, Archive *pare
 					md5.add(biosData + bios->blobs[romid].offset, bios->blobs[romid].length);
 				DEBUG_LOG(NAOMI, "Mapped %s: %x bytes at %07x", bios->blobs[romid].filename, read, bios->blobs[romid].offset);
 				found_region = true;
+				if (region == -1)
+					config::Region.override(bios->blobs[romid].region);
 			}
 			break;
 		case EepromBE16: