Diagonal box appears to be Comcast amplified distribution box, you can get rid of this IF you are not using Comcast. White box appears to be a fiber optic or satellite TV box, you may be able to get rid of this also if you are not using these services. Now a work of caution, if you are streaming from Comcast, you may not be able to remove their box even though you are not using the TV function. It would be necessary to test first.

If you don't remove the Comcast distribution box, doesn't it at least need to be repositioned so you can see the indicator lights on it? It looks like someone pushed that box out of the way to make room for the other box. I don't think Comcast uses these powered splitter boxes any longer. A neighbor of mine recently lost his cable tv service because that box failed.

By "white box", if you are referring to the lowest box then that is a UPS.

Why are you even bothering if everything seems to work good in the house? Just leave it all alone and do some gardening or fishing or golfing

Put the cover back on and pretend you never saw that box of spaghetti! You need only a Router in the house and should be streaming ! Cable is expensive and a dinosaur...

I believe you have a 5 way powered splitter. One of the white coax cables comes from a the little black box at the bottom of the cabinet. This box takes 110V in and outputs 12V through the coax. The other white coax is the signal source from the cable company. The cable company doesn't really need an amplified splitter but there may be a coax from the attic attached to an antenna which would need amplification.

If you turn the splitter over you can see which cables are input, power, and output.

This doesn't really help with your problem but at least you understand the purpose. You still need a splitter unless you only use one cable for your house.

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I don't know what service you have that needs this device. You can see if the output goes anywhere.

I’d recommend replacing that old irrigation controller with an Orbit B-Hyve controller that is mounted on the wall, outside the box. That’s easy to change out and wire, or you can pay someone to to it. The Orbit B-Hyve irrigation controller is a smart controller that knows about the weather forecasts and will automatically save you money on your water bill, paying for itself. After it pays for itself, they money you save on your water bill can be spent on something else. You can also program, control, and monitor the Orbit B-Hyve controller with your cellphone from anywhere. The smart irrigation controller has a WiFi connection, and needs to be located outside the metal shielded box, so it can use your WiFi. The Orbit B-Hyve irrigation controller is cheap, about $100 or less, depending on how many zones it has.

Most people that live in TV like to take care of their houses.

LV Battery
 

LV Box The Battery is for Centurylink which is probably not used for comcast you
can remove it and that will give you the extra room

So the wires coming out of the UPS run to the NID box outside?

Thanks all. Some great ideas. Just need to start with Comcast and see if they will do it. As I said before, I only have their internet now.

It has something to do with Century Link cable. I removed all of that when I bought the house!

Easy
 

Best option is to just close the door.

What are you going to do with the extra space???