Card with hdmi

Geforce 210 is a decent card meeting those requirements:

http://www.techpowerup.com/reviews/Inno3D/GeForce_210/2...

I have the 1GB model on one of my PCs running two monitors. It works great and cost me around $25. If you live near a microcenter, you'll find this kind of deal.

Otherwise, newegg has them for around $40:

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Don't expect much gaming performance out of the GT 210. To see other upgrade options for nongaming cards - some of which allow for a light gaming - you could go to:

http://www.upgradevideocards.com/nongaming.html

Pay particular attention to the power requirements for video cards.