diff --git a/src/machine/machine_table.c b/src/machine/machine_table.c
index d26f5e396..f47c43c35 100644
--- a/src/machine/machine_table.c
+++ b/src/machine/machine_table.c
@@ -3588,8 +3588,8 @@ const machine_t machines[] = {
         .flags = MACHINE_FLAGS_NONE,
         .ram = {
             .min = 256,
-            .max = 512,
-            .step = 256
+            .max = 1024, /* assumed; more can be added via memory expansions */
+            .step = 128
         },
         .nvrmask = 63,
         .jumpered_ecp_dma = 0,
@@ -3632,8 +3632,8 @@ const machine_t machines[] = {
         .flags = MACHINE_FLAGS_NONE,
         .ram = {
             .min = 256,
-            .max = 512,
-            .step = 256
+            .max = 1024, /* assumed; more can be added via memory expansions */
+            .step = 128
         },
         .nvrmask = 63,
         .jumpered_ecp_dma = 0,
@@ -3853,8 +3853,8 @@ const machine_t machines[] = {
         .flags = MACHINE_FLAGS_NONE,
         .ram = {
             .min = 256,
-            .max = 512,
-            .step = 256
+            .max = 1024, /* assumed; more can be added via memory expansions */
+            .step = 128
         },
         .nvrmask = 63,
         .jumpered_ecp_dma = 0,