I was better then him in when I was 12, but that was CS 1.6, wich is harder I guess, and against pretty good opponents, not first time players like in this video.
I recommend you sell all those parts, and get proper parts, AGP is ancient history,you better not spend any money on that anymore, look at me, even I went onto PCI-E, and the whole kit didn't cost me much, only about 75 bucks.
And my system can run LFS with no problem, and TDU works with minor lags at some places, here's my rig:
Motherboard: ASUS P5GDC Deluxe(Good this about this mobo is, that it runs both, DDR and DDR2)
CPU: Intel Pentium 4 540 (It's a 1 core CPU with Hyper-Threading, so it virtually has 2 cores)
RAM: 512 MB DDR(DDR2 is cheaper and better then DDR, but I had that before)
GFX: nVidia GeForce 6600 256 MB DDR
PSU: Fortron 350w(That's more then enough, because Fortron makes quality PSU-s)
And I am pretty sure that you can get parts similiar to those even cheaper in america, so you can get better parts for the same price.
I would wait for the AMD 6900 series, if the 6900 cards are too expensive, then they will atleast drop the prices of other graphics cards.
And rc10racer, that CPU cooler wont go on the AM3.