Hi and welcome to the forum
I ran up to 10 computers on my LAN using the upper end of a Verizon 1Mbps DSL connection for 3 years; so I completely understand your pain. There are some things you can do. You can completely disable WUDO and all Windows updates from coming into all your W10 computers which will help. To do this, take a look at these 2 links for instructions here:
#1:
https://support.microsoft.com/en-us/kb/3073930#bookmark-1607 #2:
Windows Update Delivery Optimization: FAQ The reason I mention this, is that pre-schedule times to bring your weekly push updates from Microsoft into your W10 computers has not historically worked well with W10 in over 2 years I've been testing it. Therefore, I'm recommending that you step up and completely turn off all your updates, and manage it manually. This is going to take some more work as you have 5 computers (don't know how many of those are W10 machines, you didn't say); but it's going to be more work than you're doing now if you have your front door open *so-to-speak* to all updates on however many W10 machines you have of the 5.
Logically speaking if you are the only person in your household, there are going to be at least several hours per night, usually when you are sleeping, when updates could come into your W10 computers. But, if you share those computers with other family members or roommates in your home; with differing schedules, you might have people using your LAN bandwidth to watch the streaming episode of NCIS at 3am. If this latter situation exists, you don't want to have any updates or as few as possible coming into your W10 machines to keep bandwidth throttling to a bare minimum.
There are other things you can do as well, such as checking to make sure that all your wireless devices are on 802.11n or 802.11ac when connecting into your wireless router. And of course, make sure your router can do either or both of these. If you're Wi-Fi router is still a 802.11g or older router, that could be chewing up your bandwidth as you entire LAN is only as fast as the slowest Wi-Fi connection on the network. So, if all 5 of your devices, hypothetically all had 802.11ac adapters but your Wi-Fi router was several years old and an 802.11g and therefore only capable of running at a max speed of 11Mbps theoretical (practical about 5/6Mbps); you'd be losing significant speed on your LAN since 1 or more of your wireless devices such as laptops/tablets are thrashing about fighting for small slices of a really slow Wi-Fi signal. You get the picture. If any of your 5 PCs that are operating in Wi-Fi connect mode have anything older than n/ac adapters, you might need to look at upgrade those devices with external usb n/ac adapters as well as upgrading your Wi-Fi router.
There are lots of free utilities such as the free Wi-Fi Analytics tool from Amped Wireless that will help you determine more details of your wireless component speeds on your LAN and where bottlenecks exist. That tool can be found here:
Amped Wireless Wi-Fi Analytics Tool Also, on your Wi-Fi network if you have a multi-story home and your are using Range Extenders, you'll need to examine those devices just like you did with your router and Wi-Fi adapters to make sure it's running n/ac speeds. Again, if you have a fast router and fast adapters on all your wireless devices, your bandwidth will suffer if 1 or more of those devices is connecting through an outdate G or older obsolete Range Extender. This is another place where my Customers blow it by not understanding the adage I gave you above; the fastest speed your can get anywhere on your LAN is a function of the slowest wireless device on the Wi-Fi portion of your network--and that includes Range Extenders along with routers and internal/external Wi-Fi device adapters!!
These are things I do on my own personal LAN as well as any Customer networks I work on or upgrade. Hopefully, it will give you some ideas on how to improve yours.
Of course you could always pay $165+ for a Geek Squad network agent to come out and re-engineer your home network, but you don't sound like you'd go that way.
Post back if you have any questions, let us know how it goes.
Best of luck,
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