Yes, but why would you?
DIRECTV’s C61K 4K Genie Mini Client will work with a non-4K TV, almost as well as it works with a 4K TV. I have personally confirmed this. However, there are some issues that may be long-term or may simply be due to the fairly early build level of the software that runs it.
When starting up, I got a message about 50% of the time that this was a non-4K TV and that 4K wasn’t supported. Well, duh. But at any rate I had to choose “Try again” from a very sparse menu in order to get to live TV.
Obviously, I was not able to select 2160p as a resolution and 4K content wouldn’t play due to HDCP (content protection) issues. So your hopes of buying a 4K pay-per-view and having it display on other TVs in non-4K resolution are basically dashed. It does not downsample 4K programming; it just ignores it.
I also saw a number of popup messages claiming content protection issues with non-4K channels but I presume those are just bugs that need to be squashed. Even though the C61K is fairly stable, it is still brand new.
Personally I would get a C61K if I thought that I was going to get a 4K TV in the next 6-9 months but beyond that I might consider getting a regular Genie client instead, as the regular clients are extremely stable and are also a lot smaller. They seem to use less energy as well, although I haven’t put the C61K on a Kill-a-Watt. I can tell you the C61K puts out a lot of heat and that’s usually a sign of excess power consumption.
It’s also worth pointing out, although I’ve said so in other articles that I would rather have a C61K than a DIRECTV Ready smart TV. I would presume that both would act about the same for the first year or so but my experience with first-generation smart TVs tells me that there comes a point where the manufacturer just can’t do a lot to upgrade them, either because of hardware limitations or because they just don’t care. I’ll tell you that my 2011 Samsung DIRECTV Ready TV is pretty much useless as a DIRECTV client, it’s too slow… but then again it always has been. More concerning is that it has lost the ability to play YouTube videos and the Netflix integration is several generations behind the current experience. There hasn’t been an update for this TV in 18 months. I’m bringing this all up because if you have a smart TV, then you’re depending on the manufacturer for all updates, even DIRECTV ones and if there’s a killer bug then they could be months behind DIRECTV in fixing it, assuming it could even be fixed on the TV. Right there, that’s why I tell my friends who like to be out on the leading edge of technology that Smart TVs are really not the way to go.