for overclocking information, check out:
according to legionhardware.com on this page (http://www.legionhardware.com/document.php?id=439) the pentium 4 630 cpu in your system has the potential to be overclocked from 3.0 ghz up to 4.5 ghz. Whether or not your computer can be overclocked and how much depends upon which motherboard and bios you have and how well your system is cooled, for starters. If you do not know very much about computer hardware, I suggest you spend a lot of time researching your hardware and hardware in general at any of the afforementioned sites.
As to whether or not it was a good deal, I honestly do not know for sure. It doesn't seem like it was a bad deal. I guess it depends upon which games you intend to play on it to answer that part of the question. I am sure that most games made in the last decade would play just fine on it, though some of the newest, most graphic intense games might exceed your radeon x700se's capabilities. I believe you could play the most intense games, but it could be a little laggy.
Hope this helps.
I recently bought a computer from ;Gateway,
3ghz 630bus ht tech 19inch tft 16-+cdrw 1gig ram keyboard mouse microsoft home 128bit 256mb ati radeon x700se
All this info means nothing to me, i bought it for