When you're choosing a rackmount battery backup for UPS critical power, the decision often comes down to two things: how much capacity you actually need and how much you're willing to spend. Two used 1500VA-class units sit on opposite sides of that trade. The Vertiv PSI5-1500RT120 is the lower-priced option and carries a 1500VA/1350W rating. The APC SMX1500RM2UNC costs $50 more, brings a Smart-UPS X 2U design, and is described as having a working display and charging function, but no internal or replacement battery is included. Here's how to pick without overpaying.
Quick verdict
If you want the higher listed wattage and a lower price, the Vertiv wins. If you want a 2U Smart-UPS X footprint with NMC in the model name and you have a replacement battery ready, the APC is the better fit. Both are used units, so condition matters as much as the specs.
At a glance
| APC Smart-UPS X | Vertiv PSI5 | |
|---|---|---|
| Listed price | $199.99 | $149.99 |
| Form factor | Rackmount Tower 2U | Rackmount/Tower |
| Listed capacity | 1500VA / 1200W | 1500VA / 1350W |
| Condition | Used | Used |
| Voltage | 120V | 100-125VAC |
Where each product wins
The seller page may include additional marketing claims. Treat this page as a shopping reference, then confirm fit, price, delivery, and returns on the seller page.
- Vertiv PSI5-1500RT120: Choose this if you'd rather have a lower-priced unit with a higher listed wattage and you're comfortable with a used commercial unit.
Product notes
APC SMX1500RM2UNC Smart-UPS X 1500VA 1200W 120V Rackmount Tower 2U NMC
The APC is the higher-priced entry in this comparison. The model name spells out the key specs: 1500VA, 1200W, 120V, 2U rackmount/tower. The description says the unit powers on, the display functions correctly, and battery charging is tested and confirmed working. What you need to know before choosing it is that no internal or replacement battery is included, so the total cost of a working UPS includes whatever battery you add. If you already have spare batteries or a source for them, the Smart-UPS X platform becomes a straightforward critical power solution. If not, that extra cost changes what this $199.99 actually buys.
Vertiv PSI5-1500RT120 1500VA/1350W Rackmount/Tower UPS
The Vertiv is priced at $149.99, which makes it the lower-priced option while carrying a 1500VA/1350W listed capacity. It's described as a rackmount/tower unit with an LCD display, and the description says it powers on, passes its built-in self-test, and charges batteries normally. It also includes pure sine wave output and automatic voltage regulation in the specification list. Because this is a used unit pulled from an active environment during an equipment refresh, expect the usual wear that comes with prior service. The lower entrance price is the main draw, but you're trading a fresh, factory-sealed state for that lower cost. For a critical power need where budget is tight, that trade can make sense.
Final choice by use case
If your rack needs the higher listed wattage and you want to keep the outlay near the lower end of the range, the Vertiv is the practical pick. If you prefer the Smart-UPS X 2U form factor and have a battery ready to install, the APC gives you that platform; just remember to add the battery cost to its price. Both are used, so inspect the unit for wear and confirm it powers on before putting critical loads on it.
