Quick Q: How good will this rig be for gaming?

[TheFuzzyFool]

I am building a computer, almost saved up enough to buy all the components

As i'm nearing the end and time of purchase, i'd really like to know how good the build I am making will be for its purpose : GAMING!

CPU : AMD Phenom II X4 955 Black Edition Socket AM3 3.2 GHz.. | Ebuyer.com
GPU : XFX HD 5850 Black Edition Dual DVI HDMI DP Out PCI-E.. | Ebuyer.com
RAM : 4GB DDR3 RAM. Depending on MOBO, I wil eventually upgrade to 8GB
MOBO: Asus M4N68T-M LE V2 Socket AM3 DDR3 Geforce 7025 VGA.. | Ebuyer.com
or: Biostar A880GU3 Socket AM3 Onboard VGA DVI HDMI USB3.0.. | Ebuyer.com
Depending on how much I save.

Already have 750W PSU, Generic DVD/RW Optical Drive, 250GB HDD(Will be adding a 1TB HDD eventually), and a Case.

So :
AMD Phenom II x4 955
ATi HD 5850
4GB DDR3 RAM
Really basic MOBO
Generic Optical Drive
Generic Case
and a HDD.

Thanks, and i'd be glad to provide and further information.

 

[TheFuzzyFool]

Sorry forgot to mention, OS will be Windows 7 64bit Home Premium.

 

[brinks]

It will run pretty much anything at high-max settings.

 

[GhOsT1321]

That will run most games on high settings, dependent on the resolution that you play at.

 

[BurningSkyline]

That will run most games on High-Max settings anywhere from 1680x1050 to 1920x1200. I would go for a higher quality motherboard. Here are some I've seen some recommended. These are off of a US site so you will need to search the model on ebuyer or whatever you use.

Newegg.com - ASUS M4A89GTD PRO AM3 AMD 890GX HDMI SATA 6Gb/s ATX AMD Motherboard
Newegg.com - GIGABYTE GA-870A-UD3 AM3 AMD 870 SATA 6Gb/s USB 3.0 ATX AMD Motherboard
Newegg.com - ASUS M4A88T-V EVO/USB3 AM3 AMD 880G HDMI USB 3.0 ATX AMD Motherboard
Newegg.com - ASRock 890GX Extreme3 AM3 AMD 890GX HDMI SATA 6Gb/s USB 3.0 ATX AMD Motherboard

EDIT: What model PSU do you have? Also, what case will you be using?