diff --git a/hw/qxl.c b/hw/qxl.c
index 47a162e4795c1882a4de2812fcdb2c7549a0d1b9..db2318e293f057a22cf1a1a8abfe48fabe2319d3 100644
--- a/hw/qxl.c
+++ b/hw/qxl.c
@@ -1959,8 +1959,8 @@ static Property qxl_properties[] = {
         DEFINE_PROP_UINT32("guestdebug", PCIQXLDevice, guestdebug, 0),
         DEFINE_PROP_UINT32("cmdlog", PCIQXLDevice, cmdlog, 0),
         DEFINE_PROP_UINT32("ram_size_mb",  PCIQXLDevice, ram_size_mb, -1),
-        DEFINE_PROP_UINT32("vram_size_mb", PCIQXLDevice, vram32_size_mb, 0),
-        DEFINE_PROP_UINT32("vram64_size_mb", PCIQXLDevice, vram_size_mb, 0),
+        DEFINE_PROP_UINT32("vram_size_mb", PCIQXLDevice, vram32_size_mb, -1),
+        DEFINE_PROP_UINT32("vram64_size_mb", PCIQXLDevice, vram_size_mb, -1),
         DEFINE_PROP_END_OF_LIST(),
 };