IBM i series Handbook page 251

Model 840 Upgrades
To 2417
From
1540
1541
1542
1543
1544
1545
1546
1540
1541
1542
1543
1544
1545
1546
Model 840 Upgrades
Model 840
To 2461
From
820
1521 M M
1522 M M M
1523 M M M M
1524 M M M M
1525 M M M M
1526 M M M M
1527 M M M M M
1521 M M
1522 M M M
1523 M M M M
1524 M M M M
1525 M M M M
1526 M M M M M
1527 M M M M M
Model 840
2418 2419
B B B
B B B
B B B
Upgrades to iSeries 8xx Servers
2420
B B B B
B B B
B B
B
B B B
B B B
B B B
B B B B
Upgrades to iSeries 8xx Servers
B B B
B B
B
221