Help Needed: Setting up Dual Monitors, Graphics Card update??

Hi there,
I need a bit of advice. I currently have a 24" Samsung monitor with my Dell Inspiron 570. I am thinking of buying another 24" monitor so that I can have a dual screen set up.
However, (please excuse my ignorance here) I have just been informed that before I buy the 2nd monitor that I also need to buy a graphics card to enable me to work the two monitors as my PC only has one socket for one monitor.
So, I was wondering if anyone could help me decide which type of graphics card to buy. I intend buying a 2nd hand one from eBay. I am NOT a gamer so I won't be needing anything too flashy but I'm open to ideas for something quite decent.
My current system reads thus:

Win7 Home Premium
AMD Athlon IIx4 630 Processor 2.80 GHz
4.00 GB RAM (3.75 GB usable)
64 Bit Operating System
After looking in Device Manager, it appears that my existing (built in???) Graphics card is ATI Radeon HD4200 - whatever that means.
Someone did suggest buying a Radeon HD4350 but again, this means nothing to me and I don't know whether:
a) they are any good, and
b) it would be compatible with my Dell Inspiron 570.

If anyone can help and offer suggestions, I'd be very grateful.
Many thanks in advance:
Skinno

 

hi plodr,
thanks for the reply, appreciated. I did mention that my computer was a Dell Inspiron 570 but am not sure exactly what other specs you would need to know. I have AIDA64 installed which tells me all the specs but not sure which exactly I need to mention. What else do you need and in which AIDA64 spec folder / category would I find them?
Here's some specs I found that might help:

Motherboard:
CPU Type QuadCore AMD Athlon II X4 630, 2800 MHz (14 x 200)
Motherboard Name Dell Inspiron 570
Motherboard Chipset AMD 785G, AMD K10
System Memory 3840 MB (DDR3-1066 DDR3 SDRAM)
DIMM1: Elpida EBJ10UE8BDF0-AE-F 1 GB DDR3-1066 DDR3 SDRAM (8-7-7-20 @ 533 MHz) (7-7-7-20 @ 533 MHz) (6-6-6-18 @ 457 MHz)
DIMM2: Elpida EBJ10UE8BDF0-AE-F 1 GB DDR3-1066 DDR3 SDRAM (8-7-7-20 @ 533 MHz) (7-7-7-20 @ 533 MHz) (6-6-6-18 @ 457 MHz)
DIMM3: Elpida EBJ10UE8BDF0-AE-F 1 GB DDR3-1066 DDR3 SDRAM (8-7-7-20 @ 533 MHz) (7-7-7-20 @ 533 MHz) (6-6-6-18 @ 457 MHz)
DIMM4: Elpida EBJ10UE8BDF0-AE-F 1 GB DDR3-1066 DDR3 SDRAM (8-7-7-20 @ 533 MHz) (7-7-7-20 @ 533 MHz) (6-6-6-18 @ 457 MHz)
BIOS Type AMI (01/25/10)

Display:
Video Adapter ATI Radeon HD 4200 (256 MB)
Video Adapter ATI Radeon HD 4200 (256 MB)
3D Accelerator ATI Radeon HD 4200 (RS880)
Monitor Generic PnP Monitor [NoDB] (H4MF105359)
Monitor LG TV (220116843009)

Motherboard Properties:
Motherboard ID 64-0100-000001-00101111-012510-ATHLON64$A785R000_BIOS DATE: 01/25/10 13:49:11 VER: 08.00.15
Motherboard Name Dell Inspiron 570

Front Side Bus Properties
Bus Type AMD K10
Real Clock 200 MHz
Effective Clock 200 MHz
HyperTransport Clock 2000 MHz
North Bridge Clock 2000 MHz

Memory Bus Properties
Bus Type Unganged Dual DDR3 SDRAM
Bus Width 128-bit
DRAM:FSB Ratio 16:6
Real Clock 533 MHz (DDR)
Effective Clock 1067 MHz
Bandwidth 17067 MB/s

Motherboard Manufacturer
Company Name Dell Computer Corporation
Product Information http://www.dell.com
BIOS Download http://support.dell.com
Driver Update http://www.aida64.com/driver-updates
BIOS Upgrades http://www.aida64.com/bios-updates

DMI:
DMI BIOS Vendor Dell Inc.
DMI BIOS Version A01
DMI System Manufacturer Dell Inc.
DMI System Product Inspiron 570
DMI System Version 00
DMI System Serial Number 82NSL4J
DMI System UUID 44454C4C-3200104E-8053B8C0-4F4C344A
DMI Motherboard Manufacturer Dell Inc.
DMI Motherboard Product 04GJJT
DMI Motherboard Version A00
DMI Motherboard Serial Number ...........
DMI Chassis Manufacturer Dell Inc.
DMI Chassis Version Not Specified
DMI Chassis Serial Number 82NSL4J
DMI Chassis Asset Tag
DMI Chassis Type Desktop Case

Thanks:
Skinno

 

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