Upgrading my rig looking for help and suggestions

[unitus77]

So i'm looking to do some upgrading on my 19 month old rig bought and built from the lovely folks at ncix.

It is for gaming, HTPC, and everyday use. I use this comp for everything but gaming is the main focus.

It was my first rig i built and yes i made some mistakes and was not a techy at the time, nor am i now but have more knowledge.

Specs:

Case: NZXT Apollo ATX Tower Case

MOBO: Gigabyte 890GPA-UD3H

CPU: AMD Phenom II X6 1090T Black Edition OC to 4.0

CPU Cooler: Corsair H50 CPU cooler

RAM: Corsair XMS3 Dominator GT 2X2GB DDR3-1600 CL 7-7-7-20 (I know crazy expensive ram i didn't need)

GPU: XFX Radeon HD 5830

HDD: Western Digital Caviar Black 1TB SATA3 6GB/S 7200RPM

SSD: Intel 335 Series 240GB

PSU: Corsair Professional HX850W Modular Silver (Yes i know but it was half off and i had big plans then never panned out)

So obvious things for me are i need to upgrade my GPU and add some more RAM. I am looking to spend >$250 on a new GPU. AMD prefered but not mandatory. Also pref factory OC.

I plan to game on a single 27 inch 1440p monitor with no desire for 3D of any kind or eyefinity setup in the foreseeable future.

Can i get a good enough GPU to do so with that price and this rig? Also i don't follow the gpu world closely

now a good time to buy or price drops coming in near future?

Now the RAM i am a bit confused about. I cannot afford more of the same ram nor do i think its even sold anymore. So what are the rules when crossing different types of ram?

8GB good enough or should i go for 14-16?

In final thoughts how long of a life do you think this thing has left in it? I know i will eventually need to get a new bigger case, new mobo and CPU. But say i slap a 7870 and 8 more gigs of ram in it could i be gaming well at 1440p for awhile?

Thanks for your time. Any ideas or insight much appreciated.

[h=1][/h]

[boogschd]

a 7870 would be your best bet

or a 7950 if you can manage (3gb > 2gb @ high res gaming)

8GB is enough for gaming ;)

[Glenwing]

8GB of RAM is more than enough for gaming. As for VRAM unless you are doing multiple monitors I don't think the 2GB vs 3GB question will come into play. 1440p is a little less than twice as heavy as 1080p. Just for perspective. I'd go with a 7950 if possible.

[bradscoolio]

Go for one of the 7870 Tahiti's, overclock the snot out of it to get the same performance as a 7950 and just get some corsair vengeance 1600 8gb cl9 cheap stuff ;) that'll be pretty good for 2k, you can turn down AA because the pixel density will fix that

[unitus77]

Thanks for the help guys. Leaning towards finding a used 7950. Any other suggestions welcome.