Looking for a discrete gpu for my PC. Can anybody recommend me one? I want it for gaming. PC specs in details?

Motherboard
Manufacturer LENOVO
Chipset Vendor Intel
Chipset Model Havendale/Clarkdale Host Bridge
Chipset Revision 02
Southbridge Vendor Intel
Southbridge Model Q57
Southbridge Revision 06
BIOS
Brand LENOVO
Version 5JKT51AUS
Date 11/2/2010
PCI Data
Slot PCI-E
Slot Type PCI-E
Slot Usage In Use
Data lanes x16
Slot Designation J6B2
Characteristics 3.3V, Shared, PME
Slot Number 0
Slot PCI-E
Slot Type PCI-E
Slot Usage In Use
Data lanes x1
Slot Designation J6B1
Characteristics 3.3V, Shared, PME
Slot Number 1
Slot PCI-E
Slot Type PCI-E
Slot Usage In Use
Data lanes x1
Slot Designation J6D1
Characteristics 3.3V, Shared, PME
Slot Number 2
Slot PCI-E
Slot Type PCI-E
Slot Usage In Use
Data lanes x1
Slot Designation J7B1
Characteristics 3.3V, Shared, PME
Slot Number 3
Slot PCI-E
Slot Type PCI-E
Slot Usage In Use
Data lanes x1
Slot Designation J8B4
Characteristics 3.3V, Shared, PME
Slot Number 4
Added (1). cpu is an intel i3 quadcore at 3.07ghz

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