System requirements for Spore taken from
http://www.spore.com/what/specs_spore
Below is listed the minimum requirements to play the game and underneath that is a list of graphics cards the game will support. I suggest you do some research and find one which suits you pricewise.
# FOR WINDOWS XP
# * 2.0 GHz P4 processor or equivalent
# * 512 MB RAM
# * A 128 MB Video Card, with support for Pixel Shader 2.0
# * At least 4 GB of hard drive space, with at least 1 GB additional space for creations.
# FOR WINDOWS VISTA
# * 2.0 GHz P4 processor or equivalent
# * 768 MB RAM
# * A 128 MB Video Card, with support for Pixel Shader 2.0
# * At least 4 GB of hard drive space, with at least 1 GB additional space for creations.
# When launching the game, some Microsoft Vista users may receive a warning about running out of address space along with a link to the Microsoft Knowledge Base. If you see this message, it is recommended that you follow the instructions and go to the website listed in the message to update your system.
# For computers using built-in graphics chipsets, the game requires at least:
# * Intel Integrated Chipset, 945GM or above.
# * 2.6 GHz Pentium D CPU, or 1.8 GHz Core 2 Duo, or equivalent.
# * 768 MB RAM
# Supported Video Cards
# NVIDIA GeForce series
# FX 5900, FX 5950
# 6200, 6500, 6600, 6800,
# 7200, 7300, 7600, 7800, 7900, 7950
# 8400, 8500, 8600, 8800
# 9600, 9800, GTX 260, GTX 280
# Intel® Extreme Graphics
# GMA 950, GMA X3000, GMA X3100
# ATI Radeon™ series
# 9500, 9600, 9800
# X300, X600, X700, X800, X850
# X1300, X1600, X1800, X1900, X1950
# 2400, 2600, 2900
# 3450, 3650, 3850, 3870,
# 4850