I'm interested in buying CHEAP but RELIABLE/DECENT laptop/desktop computers

For desktop computer:
at least 2.5 GHz and above CPU
at least 512 MB and above RAM
with decent video card

For laptop computer:
at least 1.8 GHz and above CPU
at least 2 GB and above RAM
with decent video card (if possible, not integrated ones)

Please contact me through the following:

E-mail: vinceandrewp@gmail.com (I often check my e-mail)
Mobile: (925)413-8203

Thank you!