How much of a improvment whould I get moving from a Duron 1.3Ghz to a Athlon 1700+, and whould be better off upgrading GPU from a TNT2 32mb to GeForce 4 64mb? Which whould be best for a gamer?

You actually had to ask if you'd get an improvement, upgrading from a.. "shudder" TNT2? to a Geforce?... lol scary...
1.3Ghz to 1700+, probably not noticable unless your doing some major computing.. graphics card, definately.

If you went to a 2GHz or more you would notice a bit of difference. Example, if I went to a 3GHz CPU, I would not notice it unless it was a long compile or something. Then it may not make that much difference. Now if I could go to say a 3500GHz, don't exsist yet, then I would see a bit of difference. A 4000GHz would be noticable. It generally takes about a 30% to a 50% difference for it to be noticable, unless you do graphics or something.

The biggest thing to remember is that you have to a few hundred MHz just to keep the system running. The rest is for you. Once you get to a certain point then it don't matter much. Mine spends 99.9% of it's time waiting on me, even if I'm doing something.

A video card is a good way to go. That will help your CPU and make the part you really see work faster and look better, provided you have a good monitor. I would try for a 128MB card if you can unless it is a LCD. If you have a LCD then get what is recommended for the display and let it be.

Since the difference of the CPU is not that big of a difference I would recommend the video card first. Later maybe you can get a a 2500 or so. I think the 2500+, like mine, is about $90.00. You may even want to get a faster one than that. Just watch those prices. Try to get the most bang for the buck.

Hope that helps.

That's a no-brainer! The graphics card upgrade is the way to go. I bet your frame rates will double if not more. You certainly wouldn't get that changing the CPU as your graphics card is the real bottle neck.

copied from bsd forum:

GF4Ti 5660 FPS
GF2MX 1600 FPS (Athlon 1.4G)
Ati8500 1430 FPS
GF2 Pro 1330 FPS
TNT1 760 FPS (Duron 1.2G)

and mine:
TNT2 w/o binary driver 160 FPS
TNT2 w binary driver 359 FPS

If GF2MX can get 1400 FPS, then GF4 should be 2000FPS or more. That mean it could boost the graphic performance by 6x or even more. In your case, CPU upgrade doesn't worth

Depends what games you are playing. Many games depend on both the CPU, and GPU, memory. Others depend on mostly GPU and memory.

If you are planning to do a CPU upgrade and you want to see a huge difference in speed. You will notice something that is twice the speed of your previous hardware. I think Athlon XP 2600+ or Athlon 3000+ based on the barton core will give you tons of speed for games. The Athlon XP 2600+ is cheap for its performance.

If your chipset is not atleast a nforce2, go with the GPU upgrade.

The FPS that glxgears show is not very accurate. A game will be a good benchmark but it is still an estimate.

Not only all that above, but the GF4 does more 'GL' stuff. You'll notice that your games 'somehow' look better, but you won't be able to put your finger on it. C-Strike will definately run smoother, and Q3 will work nicely.
Card first, wait on the CPU as the prices are always coming down. Be careful on the upgrade of the CPU, as not all M/B's are compatible with the new FSB's etc. A safe bet would be to make sure you have the latest bios loaded on the motherboard prior to upgrading, and then, only but a CPU that is on the recommended list at the M/B manufacturers site (if possible).
With the prices are going now, if you can hold off a little, you probably can get a 'M/B-CPU' combo for the price of the CPU now.