Gateway TG585v7 problems

[#1]

Hey all,
I have two problems with this router.
1) My gateway TG585v7 is running slow.  I don't mean the internet is slow, I mean the browser interface is slow.  When I go to log into http://192.168.1.254, it takes ages to load, a good 45 seconds.  When in the home screen, if I want to load the Game and Application Sharing menu, it will take about 30 seconds for it to load.  Why would it be running this slow?
2)  It forgets what IP Addresses games are linked with.  For example, BF3 needs specific ports to be opened for it to work for me.  I enter all the ports, and then attach it to my computer.  After about a minute, I loose connection from the internet and then when I go and check the Game and Application Sharing screen, all the applications and games have changed to totally different devices.  Why would this be?
This is with the 8.2.6.5 firmware.

[#2]

Hi theberrys,
is this a wired or wireless connection to the router?
Jojo

[#3]

Hello
I have two laptops connected wirelessly and 3 devices connected via Ethernet through a switch.  My main desktop is connected via Ethernet through that switch.  
Sorry, I don't know how to explain it better so I have drawn it XD

[#4]

It still mixes the games up and is very slow.  I have tried restarting my router but to do effect.

[#5]

Hi there,
Is the router interface slow for all the PCs or is it a specific one? Also, just to rule out the rest of the equipment, is it still slow from a single computer connected directly to the router via an ethernet cable?

[#6]

I have just tried my laptop connected to the router via Ethernet and it is still painfully slow.

[#7]

You've just described half of the problems that have made me decide to replace my TG585v7... Add to that the non-existent traffic prioritisation (currently updating a game in Steam and the connection has gone from perfect to waiting 30 seconds for a page to load), pathetic wireless range and hissy fits if too many devices connect to it....
Probably not what you wanted to hear, but after suffering through this from day one for well over a year now, I think it's time to splash out some serious money on a kickass router...

[#8]

I'm not willing to spend more money on a new router when the one provided should be sufficient.  I am still waiting for a reply from Plusnet...

[#9]

Hi theberrys,
Unless you've got a lot of custom configurations set in there it might be worth trying a factory reset to see if that sorts things (bear in mind you can back up the config before you do), but as the router's a few days off three years old we'd not be able to replace it under guarantee I'm afraid.