I'm not sure what you consider its 'potential' to be, but that FX5500 isn't a card that's up to good performance with the latest PC games, I'm afraid. It's basically not much different to an FX5200, except for the change from a 64-bit memory interface to a 128-bit memory interface.
The increased graphics memory bandwidth is an improvement, admittedly, but it still leaves the card as a good performer for older games, rather than an adequate one for new games!
I think I have a related problem . I recently reinstalled my windows xp sp1 2004 and the nvidia riva tnt 2 32mb video ram card was automatically detected and installed . Unfortunately , the graphics is continually being dark everywhere . I am looking for the exact website from which I can download a software for my graphics card and change the colour settings .
You should start by using the adjustments on your monitor itself.
But the adjustments included in the nVidia driver are certainly far superior than those included in the inbuilt driver supplied by Microsoft, and you can download a reference driver from NVida's download section
Simply download the file to your hard drive, double-click it to run the file and it will self-extract and install. Follow the prompts as necessary.
After it's installed, you can use the 'Colour correction' section of the display card's entry in 'Display properties -> Settings -> Advanced' to make the necessary changes.
Once you've done that, double click the Coolbits file you downloaded, it will ask if you're sure you want to add that information to the registry. Click Yes, then, when it's all done, reboot. (I've put a link to Coolbits below, but read on before you start).
Once you've done that, and have rebooted and are sitting back at your desktop, right click on the desktop, pick Properties, pick the Settings page, and then click the Advanced button. One of the tabbed pages in the advanced section should have the name of your video card on it, pick that page, look in the scroll box on the left, you should see tons of options. Among them, now that you've run the Coolbits registry hack, you should see 'Clock Frequencies'. In there, you can CAREFULLY overclock your card.
(A hint, unless you have a super cooled machine, don't try raising your Core speed more than say 10 or 15. Before you change it, note the number, then divide your vid card's Memory speed by your its core speed. You should come up with a number around 2.3. or so. Once you know that number, set your core speed up say 10 points higher than it was, and multiply the new core speed by the number you got by dividing memory speed by core speed, and you'll know the best number to set your memory speed to).
Fair warning, you can gain a nice boost in performance, but if you turn it up too high, your machine can lock up, or you can get visual 'artifacts' in games, (little graphic glitches), or if you are really too agressive at overclocking it, you could potentially damage your video card. So keep this in mind before you undertake this task!
I have overclocked every Nvidia card I've owned since my original GeForce 256, and never had any problems. But I'm pretty skilled at computers, and I have no less than 5 normal sized cooling fans in my machine, as well as 1 huge fan in the side blowing right down on my video card and CPU.
Again, be sure you're willing to take the risk before you try this. You might search the web to see what settings other overclockers have used on your model card successfully, too.
Here's the link to the Coolbits reg hack, in case you decide to give it a shot: