Power 7 Power Requirements
IBM Power 7 and Power 7+ power requirements by machine type: rated voltage, maximum watts, thermal output in BTU per hour, weight and rack units for the Power 720 and Power 740 across the B, C and D generations.
The interesting thing about Power 7 electrical figures is how much they moved inside one generation. A Power 720 went from 750 W in the B generation to 995 W in the D generation without changing its model name or its 4U footprint. If you are planning around a Power 7 you inherited, the letter at the end of the machine type matters more than the family name does.
Power 7 power requirements by machine type
IBM published electrical and physical ratings, Power 720 and Power 740
| Machine type | Model | Operating voltage | Max power | Max thermal | Weight | EIA |
|---|---|---|---|---|---|---|
| 8202-E4B | Power 720 | 100 - 127 or 200 - 240 V ac | 750 W | 2,560 BTU/hr | 39.5 kg | 4U |
| 8202-E4C | Power 720 | 100 - 127 or 200 - 240 V ac | 840 W | 2,867 BTU/hr | 39.5 kg | 4U |
| 8202-E4D | Power 720 | 100 - 127, 200 - 208 or 220 - 240 V ac | 995 W | 3,395 BTU/hr | 39.5 kg | 4U |
| 8205-E6B | Power 740 | 200 - 240 V ac | 1,400 W | 4,778 BTU/hr | 39.5 kg | 4U |
| 8205-E6C | Power 740 | 200 - 240 V ac | 1,570 W | 5,358 BTU/hr | 39.5 kg | 4U |
| 8205-E6D | Power 740 | 200 - 208 or 220 - 240 V ac | 1,630 W | 5,562 BTU/hr | 39.5 kg | 4U |
All models are single phase at 47 to 63 Hz. Figures are for the rack-mounted drawer; the stand-alone tower form of the same machine types weighs 50 kg. The B, C and D suffixes are POWER7 and POWER7+ refreshes of the same chassis, and each one raised the electrical ceiling. Source: IBM Power 7 server specifications.
The Power 720 is the only model here that will accept a 120 V circuit. Every Power 740 requires 200 V or better. That single distinction is the most common surprise when a 720 is replaced with a 740 in a small room that was wired for the older machine.
What replaces a Power 7, and what it draws
A Power 7 that is still running is running well past IBM support, and the facilities question is usually part of a replacement decision rather than a standalone one. The useful comparison is not watt for watt, because the modern machine does vastly more work. It is whether the room has to change at all.
Rated maximum power against likely replacements
| If you run | Rated max | Common replacement | Rated max | Room impact |
|---|---|---|---|---|
| Power 720 (8202-E4B) | 750 W | Power 11 S1112 (9242-21B) | 550 W | Lower load, same 120 V circuit works |
| Power 720 (8202-E4D) | 995 W | Power 10 S1014 (9105-41B) | 1,075 W | Broadly unchanged |
| Power 740 (8205-E6B) | 1,400 W | Power 11 S1122 (9824-22A) | 2,600 W | Higher rating, 2U instead of 4U |
| Power 740 (8205-E6D) | 1,630 W | Power 11 S1124 (9824-42A) | 2,950 W | Higher rating, far higher capacity |
Ratings are the maximum a machine is permitted to draw, not what it does draw. Where the replacement rating is higher, the measured draw and the work done per watt both move sharply in the newer machine's favor, and the rack space usually shrinks. The row worth noticing is the first one: a Power 11 S1112 is rated below the oldest Power 720 while replacing it several times over.
Planning a room that still holds a Power 7
Confirm the suffix, not the family
8202-E4B, E4C and E4D are all a Power 720 and all rated differently. Read the full machine type from the bezel or from the HMC before sizing anything, because a 33 percent difference sits between the first and the last of them.
Power supplies are the failure point now
Every Power 7 supply is more than a decade into service. Parts availability is the constraint, not capacity. Confirm redundancy is actually intact rather than assuming it, and confirm a supply can still be sourced before committing to another year.
Cooling is rarely the constraint
At 2,560 to 5,562 BTU/hr these machines are modest by current standards. A room built for a Power 7 will comfortably cool anything that replaces it, which removes one common objection to moving.
Check the tower against rack assumption
The stand-alone form weighs 50 kg against 39.5 kg for the drawer, and has no rack rail requirement. For a relocation, that changes the handling plan more than the electrical plan.
Source for every rating on this page: IBM's Power 720 and Power 740 server specifications. Replacement figures are drawn from IBM's current Power 10 and Power 11 server specifications.
Confirm what you actually have on Identify Your Power 7 and check the processor against the Power 7 CPU reference. If this is part of a replacement decision, the Power 7 sizing guide and the migration options carry the capacity side, and the end of support position sets the deadline. For the cross-generation facilities walkthrough see AS400System.com's Power server power requirements guide.