I am interested in upgrading my video card and need to replace my power supply and would like some suggestions.

Current system specs:
Intel D915GEVL motherboard
1 GB DDR2-533 DDR2 SDRAM
Intel P4 3.4GHz processor
1 Compaq 50Gb harddrive (from previous system)
1 Western Digital 120Gb harddrive (from previous system)
NVidia GeForce FX 5200 PCI (previous system didn't have AGP)
Silicon Image 0680 Ultra-133 IDE controller
Compaq 52x CD-ROM (from previous system)
Memorex DVD-ROM/CD-RW combo drive (from previous system)
ViewSonic VA520-3 LCD monitor (VGA rather then DVI)
Raidmax gaming case, forget the exact model but it came with a 420watt Raidmax PSU and 6 case fans installed
Windows XP Pro SP2

I am thinking of getting an Antec TruePower 2.0 550 watt PSU for around $100, and some brand of GeForce 6800/6600 for around $200. (Which is better, 6600 or 6800? 6800 would seem like it would be better, since the 7800 is supposed to be better then either, yet the clock speeds I'm seeing on NewEgg are higher for the 6600.)
The last video card I bought before the FX 5200 was a Voodoo 3 2000, so I'll probably be using my next video card for a long time. I think I'd like a 256 meg card if there are any good ones in my price range, since I'll probably be using it a long time. I want one with a VGA port or included adapter since my LCD doesn't do DVI. My motherboard uses PCI Express 16x, and I'm not really intending to do SLI. Standard RCA plug AV output (as opposed to S-Video) would be a plus, but not a big issue and I don't know if any video cards actually provide it.

As far as the powersupply, my current one has some bad cables and I'd like to get a PSU from a brand I trust anyways. I'm also not sure if a 420 would provide enough power with a PCI Express video card. A friend recommended an Antec when I talked with him about it a while ago, and their TruePower 2.0 series feature the new style 24 pin connector which my motherboard is designed for. I need at least 5 molex connectors, 4 for drives 1 for case fans/LEDs/Etc., and maybe more if the motherboard and/or video card need them. (I know with the 20-pin connector my PSU has the motherboard uses a molex but I don't recall if you need it when using a 24-pin connector.) I don't know for sure how much power my system actually needs, but I would hope a 550 watt PSU would be enough. Does the TruePower 2.0 550 watt PSU sound like a good buy, or is there something else you would recommend?

I'm usually more of a software guy then a hardware guy. My last system was more or less at a dead end upgrade wise, and having had problems with the Acer and Compaq's I had, I started putting this system together myself, starting with the 120Gb drive that I used to beck stuff up from the old computer. And yes, I know AMD is considered better for gaming, but their CPU naming was so confusing I gave up trying to figure it out, and this particular board included a somewhat rare feature combination that I wanted: A DDR 2 board with 4 PCI conventional slots.

1. That is a great PS that you picked out.
2.You could go with either the 6800GS http://www.newegg.com/Product/Prod [...] 6814125218 for about $195. Or you could have the 7800 Gt if you wanted to http://www.newegg.com/Product/Prod [...] 6814130256 for about $300 which comes with Quake 4. The 6800GS will play all of todays on medium-high settings, while the 7800GT willl play most on high with a great FPS.

Yeah go with 6800GS or GT, only thing is i dunno if the GS is availible for AGP. The 6600 has a higher clock speed but the 6800 series has more pipelines which greatly improve performance.

AGP isn't an issue. Lack of AGP was an issue that caused me to end up with a PCI video card last time I upgraded, which is what I'm intending to replace with a PCI Express card. That Gigabyte 6800GS looks good, and I've heard good things about the brand in general, so that's probably what I'll get when I do order it. It's been said that the 6800GS can be a bit noisy, but I doubt I'll be able to hear it over the noise of the case, PSU, and CPU fans anyways. (At the moment there are 6 case fans, 2 PSU fans, plus the CPU fan going.)