diff --git a/repos/ports/src/virtualbox5/accloff/sup.cc b/repos/ports/src/virtualbox5/accloff/sup.cc
index fc234927b..800f605e5 100644
--- a/repos/ports/src/virtualbox5/accloff/sup.cc
+++ b/repos/ports/src/virtualbox5/accloff/sup.cc
@@ -127,7 +127,14 @@ void genode_update_tsc(void (*update_func)(void), unsigned long update_us)
 
 HRESULT genode_setup_machine(ComObjPtr<Machine> machine)
 {
-	return genode_check_memory_config(machine);
+	ULONG memory_vbox;
+	HRESULT rc = machine->COMGETTER(MemorySize)(&memory_vbox);
+	if (FAILED(rc))
+		return rc;
+
+	size_t const vmm_memory = 1024ULL * 1024 * (memory_vbox + 16);
+
+	return genode_check_memory_config(machine, vmm_memory);
 }
 
 
diff --git a/repos/ports/src/virtualbox5/frontend/main.cc b/repos/ports/src/virtualbox5/frontend/main.cc
index bd5d0d2d4..299f328fb 100644
--- a/repos/ports/src/virtualbox5/frontend/main.cc
+++ b/repos/ports/src/virtualbox5/frontend/main.cc
@@ -167,8 +167,7 @@ HRESULT setupmachine(Genode::Env &env)
 
 	static Bstr gaFramebufferId[64];
 
-	unsigned uScreenId;
-	for (uScreenId = 0; uScreenId < cMonitors; uScreenId++)
+	for (unsigned uScreenId = 0; uScreenId < cMonitors; uScreenId++)
 	{
 		Genodefb *fb = new Genodefb(env);
 		HRESULT rc = display->AttachFramebuffer(uScreenId, fb, gaFramebufferId[uScreenId].asOutParam());
@@ -182,6 +181,12 @@ HRESULT setupmachine(Genode::Env &env)
 	if (FAILED(rc))
 		return rc;
 
+	/* check whether enough memory is available for VM + VMM */
+	ULONG const required_memory_vm = (13 * 1024 + 6 * memory_vbox) << 10;
+	rc = genode_check_memory_config(machine, required_memory_vm);
+	if (FAILED(rc))
+		return rc;
+
 	/* wait until VM is up */
 	MachineState_T machineState = MachineState_Null;
 	do {
@@ -209,6 +214,25 @@ HRESULT setupmachine(Genode::Env &env)
 
 	genodeConsole->init_backends(gKeyboard, gMouse);
 
+	/* check whether enough memory for the fb is available */
+	ULONG required_memory_fb = 0;
+	for (unsigned uScreenId = 0; uScreenId < cMonitors; uScreenId++)
+	{
+		IFramebuffer * aFramebuffer = nullptr;
+		HRESULT rc = display->QueryFramebuffer(uScreenId, &aFramebuffer);
+		Genodefb * fb = dynamic_cast<Genodefb *>(aFramebuffer);
+		if (FAILED(rc) || !fb)
+			continue;
+
+		required_memory_fb += fb->w() * fb->h() * 4;
+	}
+	if (!required_memory_fb)
+		required_memory_fb = 4096 * 2160 * 4;
+
+	rc = genode_check_memory_config(machine, required_memory_fb);
+	if (FAILED(rc))
+		return rc;
+
 	return rc;
 }
 
diff --git a/repos/ports/src/virtualbox5/spec/nova/sup.cc b/repos/ports/src/virtualbox5/spec/nova/sup.cc
index dde21ea4b..31d3f19b9 100644
--- a/repos/ports/src/virtualbox5/spec/nova/sup.cc
+++ b/repos/ports/src/virtualbox5/spec/nova/sup.cc
@@ -170,10 +170,11 @@ HRESULT genode_setup_machine(ComObjPtr<Machine> machine)
 	 * - second chunkid (1..2) is reserved for handy pages allocation
 	 * - another chunkid is used additional for handy pages but as large page
 	 */
-	HRESULT ret = genode_check_memory_config(machine);
-
+	size_t const vmm_memory = 1024ULL * 1024 * (memory_vbox + 16) +
+	                          (CHUNKID_START + 1) * GMM_CHUNK_SIZE;
+	HRESULT ret = genode_check_memory_config(machine, vmm_memory);
 	if (ret == VINF_SUCCESS)
-		vm_memory(1024ULL * 1024 * memory_vbox + (CHUNKID_START + 1) * GMM_CHUNK_SIZE);
+		vm_memory(vmm_memory);
 
 	return ret;
 };
diff --git a/repos/ports/src/virtualbox5/sup.cc b/repos/ports/src/virtualbox5/sup.cc
index aa7408f3b..02e08503d 100644
--- a/repos/ports/src/virtualbox5/sup.cc
+++ b/repos/ports/src/virtualbox5/sup.cc
@@ -376,30 +376,16 @@ void genode_VMMR0_DO_GVMM_REGISTER_VMCPU(PVMR0 pVMR0, VMCPUID idCpu)
 }
 
 
-HRESULT genode_check_memory_config(ComObjPtr<Machine> machine)
+HRESULT genode_check_memory_config(ComObjPtr<Machine>,
+                                   size_t const memory_vmm)
 {
-	HRESULT rc;
-
-	/* Validate configured memory of vbox file and Genode config */
-	ULONG memory_vbox;
-	rc = machine->COMGETTER(MemorySize)(&memory_vbox);
-	if (FAILED(rc))
-		return rc;
-
 	/* Request max available memory */
-	size_t memory_genode = genode_env().pd().avail_ram().value >> 20;
-	size_t memory_vmm    = 28;
+	size_t const memory_available = genode_env().pd().avail_ram().value;
 
-	if (memory_vbox + memory_vmm > memory_genode) {
-		using Genode::error;
-		error("Configured memory ", memory_vbox, " MB (vbox file) is insufficient.");
-		error(memory_genode,              " MB (1) - ",
-		      memory_vmm,                 " MB (2) = ",
-		      memory_genode - memory_vmm, " MB (3)");
-		error("(1) available memory based defined by Genode config");
-		error("(2) minimum memory required for VBox VMM");
-		error("(3) maximal available memory to VM");
-		return E_FAIL;
-	}
-	return S_OK;
+	if (memory_vmm <= memory_available)
+		return S_OK;
+
+	Genode::error("Available memory too low to start the VM - available: ",
+	              memory_vmm, "MB < ", memory_available, "MB requested");
+	return E_FAIL;
 }
diff --git a/repos/ports/src/virtualbox5/sup.h b/repos/ports/src/virtualbox5/sup.h
index 6133c81a7..05f12958d 100644
--- a/repos/ports/src/virtualbox5/sup.h
+++ b/repos/ports/src/virtualbox5/sup.h
@@ -26,7 +26,7 @@
 #include "MachineImpl.h"
 HRESULT genode_setup_machine(ComObjPtr<Machine> machine);
 
-HRESULT genode_check_memory_config(ComObjPtr<Machine> machine);
+HRESULT genode_check_memory_config(ComObjPtr<Machine> machine, size_t);
 
 /**
  * Returns true if a vCPU could be started. If false we run without