Trouble with Multiple Wireless Devices-Ubee DOCSIS 3

[Erous]

So I just switched to Time Warner Cable extreme wideband 50Mbps. It's great so far for the PC that is directly connected. I am having trouble keeping a consistently high speed for my Wireless N devices in the house.

For example, I'm posting this on my Wireless N laptop, the speed on the wireless network status fluctuates from 72Mbps to 104, to 6. Speedtest.net comes back with with a whopping 10Mbps. If I go upstairs, my PC with a USB Dual band wireless N adapter is getting between 45-50 Mbps via Speedtest, with the wireless adapter hitting 300Mbps as a connection(as it should for wireless N). My son who has a newer USB wireless N adapter is only getting on average 13 Mbps via speedtest. The hardware connection is getting 51Mbps.

All drivers are up to date for the Wireless N adapters.

I need some help for those who have a similar setup, or experience for maximizing the Wireless N speeds. The DOCSIS 3 modem/router is a Ubee model from Time Warner with Wireless N capabilities.

My settings for the modem:

Encryption: WPA/WPA2 AES
802.11 Band: 2.4Ghz
Bandwidth: 40 Mhz
Sideband for Control Channel: Upper
Control Channel 5

Any recommendations on settings to Maximize the wireless N connectivity for the devices?
Should I bypass the wireless portion of the modem and go with my Dual Band Linksys instead? (If I go this route, how do I setup the Ubee to allow this?)

I just want consistency is speed going throughout the house for the wireless devices or the most optimized performance method to get the most out of my increased bandwidth.

[Cyanotical]

speedtest.net is not reliable under any circumstance, dont use it

if you want to test your bandwidth, download a large file from a high traffic site, and convert the byte/second into bits/second

your wireless throughput will vary based on your location relative to the wifi point, if you have wireless phones and/or bluetooth, change your wifi frequency to 5Ghz, otherwise there is nothing you can do about it

[Erous]

speedtest.net is not reliable under any circumstance, dont use it

if you want to test your bandwidth, download a large file from a high traffic site, and convert the byte/second into bits/second

your wireless throughput will vary based on your location relative to the wifi point, if you have wireless phones and/or bluetooth, change your wifi frequency to 5Ghz, otherwise there is nothing you can do about it

I thought about using 5Ghz, but I think one of my devices doesn't support dual band and it's my understanding 5Ghz doesn't work well through walls. I swapped back to 20Mhz from 40 and surprisingly am getting more reliable results.

[Cyanotical]

I thought about using 5Ghz, but I think one of my devices doesn't support dual band and it's my understanding 5Ghz doesn't work well through walls. I swapped back to 20Mhz from 40 and surprisingly am getting more reliable results.

well, the farther away your current channel is from your phones/bluetooth/other wifi signals, the better your connection is going to be, but please understand with wireless you will never get consistent speeds all over your house, you can get near consistent by disabling other signal sources and removing all physical objects, (including walls) between you and your access point, but even that gets affected to a small degree by the sun and the earth's EM field, as well as microwaves, blenders, florescent lights, speakers, and anything else that generates noticeable EMI,

there is also the amount of devices on your WAP, most home routers are designed to handle 2-3 wireless devices, so if you are putting 10-15, it may be processing lag on your router's hardware

5Ghz would be the ideal frequency, it will go through walls, just not 1 foot thick solid brick walls

[Erous]

I was ales reading that 40Mhz bandwidth is not ideally used with 2.4 ghz. That may have been the root of my problem. I'm going to have to end up getting an adapter for our laptop to handle 5 ghz before I commit