diff --git a/src/config.sh b/src/config.sh
index e074afa..91c4529 100644
--- a/src/config.sh
+++ b/src/config.sh
@@ -8,7 +8,7 @@ set -Eeuo pipefail
 DEF_OPTS="-nodefaults"
 SERIAL_OPTS="-serial $SERIAL"
 USB_OPTS="-device $USB -device usb-kbd -device usb-tablet"
-RAM_OPTS=$(echo "-m $RAM_SIZE" | sed 's/MB/M/g;s/GB/G/g;s/TB/T/g')
+RAM_OPTS=$(echo "-m ${RAM_SIZE^^}" | sed 's/MB/M/g;s/GB/G/g;s/TB/T/g')
 CPU_OPTS="-cpu $CPU_FLAGS -smp $CPU_CORES,sockets=1,dies=1,cores=$CPU_CORES,threads=1"
 MON_OPTS="-monitor $MONITOR -name $PROCESS,process=$PROCESS,debug-threads=on"
 MAC_OPTS="-machine type=${MACHINE}${SECURE},dump-guest-core=off${KVM_OPTS}"