Video Card Questions !Need Help!

First off, I have a P4 2.8ghz processor, 1 gig of ram, 160gb hd, and a Nvidia 3D Fuzion 6200 128Mb PCI video card. I recently upgraded from a Radeon 9250.

I am experiencing some problems with Steam games. In Counter-Strike Source and Half-Life 2 I get major hickups that come and go every minute or so. Not too annoying, but there is some serious slowdown when it happens. It never happened to my other graphics card, the Radeon 9250. Also, I'm not too sure if its an artifact or not, but both games make the weapons and npc's look sort of blue-ish. Is there any way of fixing this or helping the slowdown?

My second question is whether or not I can put both of my video cards into my system at the same time and switch them on and off. I need the Nvidia to play BF2 and other games that the Radeon doesn't support, but I feel the ATi plays my favorite game, Counter-Strike Source, the best.

I have the Nvidia driver 84.21, because everyone has suggested that to me and it seems to be fine. I have a 200 or 250 W power supply, (which may be a problem, I'm not too sure). It would be a great help if anyone could give any suggestions. Thanks

Can you tell us how hot the card(s) are running? These sort of problems are common when the card is overheating or not getting enough power.
Can you tell us your psu's wattage and the amps on it's 12v rail (this info is on the psu sticker)?
Unfortunately afaik you can't have two cards in your system and switch between them. I don't even think you can have the two cards sitting in the motherboard, even if you only have one set of drivers installed, but someone might need to correct me on that.

The problem is your video card is only PCI. I am assuming that that your motherboard doesn't have an AGP or PCI-E slot.

as far as I know the 6200 is the best PCI card you can get. it performs about the same as the radeon 9250, but it's DX9 compliant.

I'm not sure about the "video card switching", you may be able to plug them both in and use the display properties control panel to alternate between the two, or they may not work at all.

as far as the power supply is concerned. 200w is weak, and is probably just cutting it for your system. but unless your computer is crashing, then it's probably doing ok.

my suggestion is to ugrade your machine. there is no hope for your rig to ever play games at any decent quality level. I'm guesing that your CPU is socket-478. if you don't want to build new, then another option is to simply upgrade the motherboard to one with an AGP8X slot, which will allow you keep your CPU and allow the use of a good video card.