I'd like to find out from you guys (in layman terms) if getting a Cat6 cable would make a difference in my current setup (I'm guessing I currently  have a Cat5 cable...will check tonight) and not very familiar with all the differences in using these.  
 
My router: Asus RT-AC66u https://www.asus.com/us/Networking/RTAC66U/specifications/ 
My Ethernet Adapter: Plugable USB 3.0 Ethernet Adapet http://plugable.com/products/usb3-e1000 (arriving tomorrow)
My internet Speed: Download 35Mbps and Upload 2Mbps 
I also have another (older) PC and printer on the network using a wireless connection
 
Given these specs, would getting a Cat6 cable make a big/small/no difference?
 
TIA

In all honesty it depends on length of run and if you are using gigabit network.
 
See this for Wikipedia
 
Category 6 cable, commonly referred to as Cat 6, is a standardized cable for Gigabit Ethernet and other network physical layers that is backward compatible with the Category 5/5e and Category 3 cable standards.[1] Compared with Cat 5 and Cat 5e, Cat 6 features more stringent specifications forcrosstalk and system noise.[1] The cable standard provides performance of up to 250 MHz and is suitable for 10BASE-T, 100BASE-TX (Fast Ethernet),1000BASE-T/1000BASE-TX (Gigabit Ethernet), and 10GBASE-T (10-Gigabit Ethernet).[1]
 
 

I think Rain and his wife are on Cat 8 or 9 by now...

Cat 6 would let you run gigabit per second speeds more reliably. But what are you connecting to? If it is your internet service, then the speed the service provider sells you is the limit regardless of how fast your router is capable of transferring to the modem. If you have several computers on your network, and if all of them have gigabit network cards/chips you can use that router to get data between them at gigabit speeds, but if you have computers with 100 mbs connections, your router will only talk to them at the slower speed. If your router is only going to be talking at 100 mbs then Cat5 should work. The difference in cost is negligible. You should be able to get either for about a quarter a foot with connectors and much less in bulk if you are willing to crimp on your own.  

I believe all my devices on my network support gigabit functionality. The PC my router & cable modem box is connected to is only 2 ft. away. The 2nd pc & printer are in another room (about 25 ft. away), but they are connected wirelessly. Yes, I'll be connecting via my internet service (Brighthouse Network).
 
This 2nd PC is wireless connected via the Edimax EW7822-UAC: http://www.edimax.com/edimax/merchandise/merchandise_detail/data/edimax/au/wireless_adapters_ac1200_dual-band/ew-7822uac/

You should be able to get a pretty fast wireless connection with that setup. 802.11ac will theoretically give you a gigabit transfer rate, but because radio transmission is subject to transfer errors and interference, requiring re-sending of lost packets, the practical speed is less. Your USB 3 adapter claims to get 867 Mbs but your experience may vary. Still a good connection to the router is a good thing. For a short run, it may not make much difference what cable you use, but for a couple of bucks you can get a Cat6 patch cable.
http://www.newegg.com/Product/Product.aspx?Item=N82E16812270013
 

On the wired side, you do NOT need Cat6 for your setup. I had my house pre-wired with Cat5e between the two floors, and connect my studio router (upstairs), via Cat5e (PC to router, and router to wall (which is Cat5e)) to my cable modem/router (downstairs), which is connected to my ISP at 75MB/sec down, 7.5 MB/sec up. Works fantastic.
 
The "capability/rating" of internal gear is irrelevant. The fastest actual speeds are governed by your connect rate, which, at a very fast 35 MB/sec, is half the speed I run no problemo, and a tenth the speed I COULD run no problemo, on Cat5e.
 
If there's no difference in price, put in Cat6. If there is a meaningful difference in cost, save the money.
 
My $0.02.
 
And to some I shall not name...worth far less. 

Thanks David & John.......since these Cat6 cables are fairly cheap, I'll get some. I'll be happy with the current 35mbs if I can get all of it.....waiting for my Plugable to arrive tomorrow. :))

Hi,
 
I'm not sure I would do Cat6 at home at all ... the network demands off a Cable/DSL are not strong enough to be useful for the bigger and better cable and network design, which is (more or less) designed for the huge offices and exchange points, where the speed and the passing of data is more critical.
 
This is my understanding, so, if it is not totally correct, please dismiss it.

Thanks Mosh, I'm not sure if I do need the Cat6 as the Cat5e seems to be working quite well. I did a speedtest last evening and was getting consistent results with 40Mbs download and slightly over 2Mbs. uploading. I may just get a few Cat6 cables if they're really cheap, but not necessary.
 
I have to say that the people at Plugable (including the owner have excellent customer service). Before my device even arrived, I got an email from the owner of the company with a link to the latest drivers (although it wasn't needed as Win 10 has these drivers already built in) and also all the contact info needed in case there were issues.
 
I was having intermittent internet connection/loss of connection since I upgraded to Win 10 and Plugable support was also trying to sort this issue out.....to no avail. They've sent a new USB 3.0 adapter (should be here in 2 days) in case the one I have is defective and all of this was done very quickly/efficiently.
 
However, I found out that my internet issue was simply a network setting that had to be unchecked for it to work.......which btw, a 16 yr. old guy on the Windows Ten forums was able to solve:
 
 
Under "Networking", click the "Configure" button. Go to "Power Management" and uncheck the box that reads "Allow the computer to turn off this device to save power" 
 
 
 
Now, I'm up and running full speed!! Wooohoooo!! :))