diff --git a/Core/ELF/ParamSFO.cpp b/Core/ELF/ParamSFO.cpp
index 4c2b65fa9b93..7d9387a97d49 100644
--- a/Core/ELF/ParamSFO.cpp
+++ b/Core/ELF/ParamSFO.cpp
@@ -86,6 +86,14 @@ u8* ParamSFOData::GetValueData(std::string key, unsigned int *size)
 	return it->second.u_value;
 }
 
+std::vector<std::string> ParamSFOData::GetKeys() {
+	std::vector<std::string> result;
+	for (const auto &pair : values) {
+		result.push_back(pair.first);
+	}
+	return result;
+}
+
 // I'm so sorry Ced but this is highly endian unsafe :(
 bool ParamSFOData::ReadSFO(const u8 *paramsfo, size_t size)
 {
diff --git a/Core/ELF/ParamSFO.h b/Core/ELF/ParamSFO.h
index e58f28d81708..956ebbab14b0 100644
--- a/Core/ELF/ParamSFO.h
+++ b/Core/ELF/ParamSFO.h
@@ -34,6 +34,8 @@ class ParamSFOData
 	std::string GetValueString(std::string key);
 	u8* GetValueData(std::string key, unsigned int *size);
 
+	std::vector<std::string> GetKeys();
+
 	bool ReadSFO(const u8 *paramsfo, size_t size);
 	bool WriteSFO(u8 **paramsfo, size_t *size);
 
diff --git a/Core/MemMap.cpp b/Core/MemMap.cpp
index 9a90c2b8a82d..e07fc65bb832 100644
--- a/Core/MemMap.cpp
+++ b/Core/MemMap.cpp
@@ -340,7 +340,7 @@ void Init()
 
 void DoState(PointerWrap &p)
 {
-	auto s = p.Section("Memory", 1, 2);
+	auto s = p.Section("Memory", 1, 3);
 	if (!s)
 		return;
 
@@ -348,7 +348,8 @@ void DoState(PointerWrap &p)
 		if (!g_RemasterMode)
 			g_MemorySize = RAM_NORMAL_SIZE;
 		g_PSPModel = PSP_MODEL_FAT;
-	} else {
+	} else if (s == 2) {
+		// In version 2, we determine memory size based on PSP model.
 		u32 oldMemorySize = g_MemorySize;
 		p.Do(g_PSPModel);
 		p.DoMarker("PSPModel");
@@ -359,6 +360,17 @@ void DoState(PointerWrap &p)
 				Init();
 			}
 		}
+	} else {
+		// In version 3, we started just saving the memory size directly.
+		// It's no longer based strictly on the PSP model.
+		u32 oldMemorySize = g_MemorySize;
+		p.Do(g_PSPModel);
+		p.DoMarker("PSPModel");
+		p.Do(g_MemorySize);
+		if (oldMemorySize != g_MemorySize) {
+			Shutdown();
+			Init();
+		}
 	}
 
 	p.DoArray(GetPointer(PSP_GetKernelMemoryBase()), g_MemorySize);
diff --git a/Core/PSPLoaders.cpp b/Core/PSPLoaders.cpp
index 82a8f3806855..7b1c8130a89d 100644
--- a/Core/PSPLoaders.cpp
+++ b/Core/PSPLoaders.cpp
@@ -102,20 +102,53 @@ void InitMemoryForGameISO(FileLoader *fileLoader) {
 	{
 		std::vector<u8> paramsfo;
 		pspFileSystem.ReadEntireFile(sfoPath, paramsfo);
-		if (g_paramSFO.ReadSFO(paramsfo))
-		{
+		if (g_paramSFO.ReadSFO(paramsfo)) {
+			// TODO: Check the SFO for other parameters that might be useful for identifying?
 			gameID = g_paramSFO.GetValueString("DISC_ID");
 
 			for (size_t i = 0; i < ARRAY_SIZE(g_HDRemasters); i++) {
-				if(g_HDRemasters[i].gameID == gameID) {
+				if (g_HDRemasters[i].gameID == gameID) {
 					g_RemasterMode = true;
 					Memory::g_MemorySize = g_HDRemasters[i].MemorySize;
-					if(g_HDRemasters[i].DoubleTextureCoordinates)
+					if (g_HDRemasters[i].DoubleTextureCoordinates)
 						g_DoubleTextureCoordinates = true;
 					break;
 				}
 			}
-			DEBUG_LOG(LOADER, "HDRemaster mode is %s", g_RemasterMode? "true": "false");
+			if (g_RemasterMode) {
+				INFO_LOG(LOADER, "HDRemaster found, using increased memory");
+			}
+		}
+	}
+}
+
+void InitMemoryForGamePBP(FileLoader *fileLoader) {
+	bool useLargeMem = false;
+
+	// TODO: Change PBPReader to read FileLoader objects?
+	std::string filename = fileLoader->Path();
+	PBPReader pbp(filename.c_str());
+	if (pbp.IsValid() && !pbp.IsELF()) {
+		size_t sfoSize;
+		u8 *sfoData = pbp.GetSubFile(PBP_PARAM_SFO, &sfoSize);
+		if (sfoData) {
+			ParamSFOData paramSFO;
+			paramSFO.ReadSFO(sfoData, sfoSize);
+
+			// This is the parameter CFW uses to determine homebrew wants the full 64MB.
+			int memsize = paramSFO.GetValueInt("MEMSIZE");
+			useLargeMem = memsize == 1;
+
+			delete [] sfoData;
+		}
+	}
+
+	if (useLargeMem) {
+		if (Memory::g_PSPModel != PSP_MODEL_FAT) {
+			INFO_LOG(LOADER, "Homebrew requested full PSP-2000 memory access");
+			Memory::g_MemorySize = Memory::RAM_DOUBLE_SIZE;
+		} else {
+			WARN_LOG(LOADER, "Homebrew requested full PSP-2000 memory access, ignoring in PSP-1000 mode");
 		}
 	}
 }
diff --git a/Core/PSPLoaders.h b/Core/PSPLoaders.h
index 3dce913c0815..400df80d6576 100644
--- a/Core/PSPLoaders.h
+++ b/Core/PSPLoaders.h
@@ -24,3 +24,4 @@ class FileLoader;
 bool Load_PSP_ISO(FileLoader *fileLoader, std::string *error_string);
 bool Load_PSP_ELF_PBP(FileLoader *fileLoader, std::string *error_string);
 void InitMemoryForGameISO(FileLoader *fileLoader);
+void InitMemoryForGamePBP(FileLoader *fileLoader);
diff --git a/Core/System.cpp b/Core/System.cpp
index 95e3eb6ca101..5d726ba2ad85 100644
--- a/Core/System.cpp
+++ b/Core/System.cpp
@@ -177,10 +177,7 @@ void CPU_Init() {
 
 	// Default memory settings
 	// Seems to be the safest place currently..
-	if (g_Config.iPSPModel == PSP_MODEL_FAT)
-		Memory::g_MemorySize = Memory::RAM_NORMAL_SIZE; // 32 MB of ram by default
-	else
-		Memory::g_MemorySize = Memory::RAM_DOUBLE_SIZE;
+	Memory::g_MemorySize = Memory::RAM_NORMAL_SIZE; // 32 MB of ram by default
 
 	g_RemasterMode = false;
 	g_DoubleTextureCoordinates = false;
@@ -209,6 +206,17 @@ void CPU_Init() {
 	case FILETYPE_PSP_DISC_DIRECTORY:
 		InitMemoryForGameISO(loadedFile);
 		break;
+	case FILETYPE_PSP_PBP_DIRECTORY: {
+		// TODO: Can we get this lower into LoadFile?
+		std::string ebootFilename = loadedFile->Path() + "/EBOOT.PBP";
+		FileLoader *tempLoader = ConstructFileLoader(ebootFilename);
+		InitMemoryForGamePBP(tempLoader);
+		delete tempLoader;
+		break;
+	}
+	case FILETYPE_PSP_PBP:
+		InitMemoryForGamePBP(loadedFile);
+		break;
 	default:
 		break;
 	}