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APC BX850M Back-UPS Pro 850 VA 510 Watts 8 Outlets Uninterruptible Power Supply (UPS)

Ships from United States. Most customers receive within 6-8 days.

Sold and Shipped by Tech For Less a-seller

Purchases from these Sellers are generally covered under our Newegg Marketplace Guarantee.
Marketplace Seller
  • 850 VA 510 Watts
  • 4 x Battery Backup Outlets
  • 4 x Surge Protected Outlets
  • Input 120V / Output 120V
  • Automatic Voltage Regulation (AVR) preserves battery life and maximizes runtime by correcting low voltages without discharging the battery

  • Overview
  • Specifications
  • Warranty & Returns
  • Reviews

Learn more about the APC BX850M

Warranty, Returns, And Additional Information
  • Warranty
  • Limited Warranty period (parts): 2 years
  • Limited Warranty period (labor): 2 years
  • Read full details
Ownership: 1 week to 1 month
Verified Owner
5/ 5
Great product! Easy to setup and use! 5/23/2020 1:14:07 PM

Overall Review: I bought this to replace my old APC UPS. This UPS runs great!! I always rely on APC to deliver high quality UPSes.

Did you find this review helpful?
Ownership: 1 week to 1 month
Verified Owner
5/ 5
Easy set up, Good product, great customer service 4/10/2020 12:15:04 PM

Pros: Product was easy to set up and use - it is used for my hardware firewall and routers. No-hassle return - see below.

Cons: First shipment did not work. Began smoking immediately upon plugging it in.

Overall Review: Original shipment was returned, and the second product, reviewed here, works great

Did you find this review helpful?
1/ 5
Don't do it 1/31/2020 5:40:39 AM

Pros: Battery backup works ok

Cons: They DID NOT honor warranty after a lightning strike damaged 'protected' equipment.

Overall Review: If I could give them negative eggs it would be a -3.

2 out of 3 people found this review helpful. Did you?
Manufacturer Response:
We are very sorry to hear of any trouble you experienced with this unit. It sounds like you may have contacted APC directly already, however this does not sound like our usual response for claims. If you have already submitted a claim and are unhappy with the resolution, please reach back out to our claims department and they would be happy to take another look at your claim. If you have not submitted a claim, please contact us directly via email at for assistance with filing an equipment protection policy claim. We hope to hear from you soon!
Ownership: 1 week to 1 month
Verified Owner
4/ 5
old product 1/26/2020 2:14:50 PM

Pros: I like this style APC backup. It is a compact design and I now have 3 of them. They have worked well.

Cons: The battery was already 18 months old when I received the backup. The stated life expectancy of the battery is 3 to 5 years. I have already lost a large amount of the life of the battery.

Overall Review: I would recommend APC backups but buy from a store which keeps a fresher inventory.

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Ownership: more than 1 year
Verified Owner
5/ 5
11/30/2019 10:09:36 AM

Pros: At my battery replacement age of this product.. I bought this in 2010 it seems, and pretty sure this is my first time replacing the battery.
Has done its job all these years.

Cons: The front panel display you see is plastic and can slide off to reveal the actual LCD screen, this snapped in half on me a few years ago when I was moving the unit around. Cosmetic issue. No big deal.

1 out of 1 people found this review helpful. Did you?
Ownership: more than 1 year
Verified Owner
5/ 5
Great UPS! 11/28/2019 9:43:29 AM

Overall Review: -Power occasionally going out forced me to buy this a few years back. Alas it has saved me many times, and maybe quite literally did when a hurricane hit
-Feature rich, and plenty of juice to power my desktop, my monitors, and all peripherals
-Has enough juice to power everything for about an hour
-It's very heavy. But that is to be expected, this is not a mobile UPS.

1 out of 1 people found this review helpful. Did you?
Ownership: 1 month to 1 year
Verified Owner
5/ 5
Works as expected! 11/19/2019 7:05:32 AM

Pros: Already had a couple of power outages from thunder storms recently and this kept my server running without a hitch!

I also like being able to see how much of a load is hooked up to it and how much time it's expected to have with the current load.

Cons: Only big complaint I have is that i wish the outlets were rotated 90 degrees! With the current setup, I have my modem, router, & my server's power supplies hooked up to the battery. I wanted to be able to hook up a monitor to it, but due to my modem and router's power supplies, i had to force them on both the top-most and bottom-most outlets or else they would've taken up the other 3 outlets. They are both large enough it overlaps the outlet next to it too, so only the center outlet is available essentially. Plus, the power supply extends past the UPS's bottom edge, so it is now sitting on its side instead of upright. Not only that, but the other power supply at the top blocks the RJ45 input & output because of this! Although I don't find that to be as big of a deal since I have the modem's co-axial hooked up. It just would've been an extra safety net if I could've had it hooked up.

I've heard the complaints of other reviewers about the loud alarm when it goes off, but I don't need it, so I muted it with the button up top.

Overall Review: Regardless of the big complaint, I'm very happy with it and it works as expected. Very useful and much needed for my 24/7 server!

11/19/2019 Edit: Still operating fine as usual! I decided to hook up a surge protector to the battery so that I can hook up everything plus the two monitors, so now it's standing upright like it should be!

As far as run times go with this hooked up (Modem, Router, PC, and two monitors) and battery at ~100%...

With the monitors turned off (~170 Watts): ~37 Minutes, ~23% Load
With the monitors turned on (~210 Watts): ~29 minutes, ~19% Load

3 out of 3 people found this review helpful. Did you?
Ownership: 1 month to 1 year
Verified Owner
5/ 5
WORTH It! 10/6/2019 7:45:53 AM

Pros: -Front panel screen with info that you can cycle with one of the buttons is very handy.
-Connect it to you PC and install the software for more info. You can also have it do certain things when the power goes out and how much of a wait before it acts... Basically it integrates with Windows power saving functions, the sleep time, screen off and hibernation... That sort of thing. Also shows you your power consumption and how much money it's costing to run what is connected.
-Handles my Gaming PC and G-SYNC monitor for about 6-8 minutes. i7 6700k @ 5.0GHZ, ASUS MAXIMUS VIII HERO ALPHA, ASUS ROG STYRIX GTX 1080 TI Overclocked heavily, 32GB DDR4 @3200MHz, Coolermaster 360mm AIO with ARGB fans and pump head. 7 fans, 3 120mm REVEEN (yellow fin ones), 3 ARGB and controller 120mm Coolermaster on the AIO, the AIO pump, 5 HDDs - 3 Adata SU800 512GB in RAID 5, 2 - 2TB Seagate HDD 7200 rpm. Lots of external USB devices.

Cons: In my use case, a longer power cable though it should be fine for most.

Overall Review: -Performs better than expected.
-Solid choice for a gaming pc setup.
-Software is a nice addition.

5 out of 5 people found this review helpful. Did you?
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