Ok so i need a good idea for a desktop gaming computer.....

[JogaBonito1502]

Monitor: Acer 20" 5ms: $160
OS: Vista Home Premium 64bit OEM: $100
CPU: Intel C2D E8500: $190
MOBO: Gigabyte GA-EP35-DS3L: $85
HSF: Xigmatek HDT-S1283: $40
PSU: Antec Neo Power 500W: $70
RAM: G. Skill (2x2GB) 800Mhz DDR2: $60
GPU: Palit HD4850: $170
HDD: Samsung Spinpoint F1 320GB: $55
CASE: Cooler Master Centurion 5: $50

Total : $980

I know it's over your budget, but I highly recommend this if you can stretch the money. If you can get 1050 that would be even better because I can switch in the original motherboard I had selected. If you want, I'll switch over to AMD, fit your budget, and get faster RAM. Unfortunately, the processor won't have as good cache as an Intel one.

edit: Price excludes fans.

 

[Teny]

My setup?
Intel Build
Optical Drive - LG Black 22X DVD Burner - $27

Case - COOLER MASTER Elite 330 - $40

CPU - Intel Core 2 Duo E8400 - $170

HDD - SAMSUNG Spinpoint F1 HD322HJ 320GB - $55

Keyboard - Saitek Eclipse - $35

Mouse - Logitech SBF-96 Black 3 Buttons 1 x Wheel USB Wired Optical Mouse - $9

RAM - G.SKILL PI Black 4GB (2 x 2GB) - $70

Monitor - Hanns·G HW-173DBB Black 17" 8ms Widescreen LCD Monitor - $140

Motherboard - BIOSTAR TForce TP45D2-A7 - $100

Power Supply - Antec True Power Trio - $80

Graphics card - HIS Hightech H485QT512P Radeon HD 4850 512MB - $180

Speaker - Logitech LS21 7 watts RMS 2.1 Stereo Speaker System - $23

Total - $901.15 (Before shipping unfortunately....).
you could probably change some things to the downgraded version. I forgot to add the Heatsink with the retention bracket, but if you dont plan to OC, stock cooling should be efficient enough, though it might be hard to do those push pins, took me like half an hour...
AMD will be about $100+ cheaper, or have better parts for almost the same price.

I will do an AMD build for you later... maybe, depends if im in the mood.
EDIT - oops... forgot the OS... guess its kind of hard choosing the parts for under $900 when you dont have the peripherals...
I will redo my list later.