The main issue in terms of compatability between your computer and a video 
card is to know whether it accepts AGP or PCI-E video cards.  The second 
question would be what power rating is for your Power Supply (and 
secondarily whether it has a PCI-E video card power cable).  Is this a 
mid-sized tower or a mini-tower?  What video card is currently in this 
computer?

Since I don't know enough about what your limitations are, I'll simply make 
some general comments at this point.  ATI/AMD and Nvidia have both released 
a number of new video cards selling in the $150-$250 range, making this 
market very competitive, now.  The AMD cards are the 3850 and the 3870, 
Nvidia's new cards are the 8800GT, 8800GTS 512mb (not the earlier 320mb and 
640mb models), and the 9600GT.

Review sites like Anandtech have quite a bit of information on these cards. 
They all require a PCI-E video card power connector, however, since they 
draw more power than can be supplied through the motherboard slot.

8800GT: http://www.anandtech.com/video/showdoc.aspx?i=3140
3850 & 3870: http://www.anandtech.com/video/showdoc.aspx?i=3151
9600GT: http://www.anandtech.com/video/showdoc.aspx?i=3234
And, Tom's Hardware has some video card comparison charts:
http://www.tomshardware.com/charts/graphics-cards/warhammer-mark-of-chaos-v1-6,581.html

With these newer video card, you may find that your system bottleneck 
becomes your CPU, especially at lower resolutions.  Sometimes trying to 
upgrade an older, inexpensive computer from makers like Dell and HP is not 
worth the trouble and the expense.  The money could be put to better use 
starting over.  Often, these systems were never intended to be a game 
machines, and they have very limited headroom for upgrading.

John Sproule

-----------Original Message Below---------

Date:    Thu, 1 May 2008 18:24:26 -0500
From:    Melani Gump <[log in to unmask]>
Subject: Re: Video Cards

Hi,
I have a Dell Dimension 5100.  I was wanting to know what a really good (and
cheap) graphics card would be that is compatible to my computer.  I would
like at least 512MB in ram and at least 6800 GT.
Can you help?
Thank you,
Melani

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