Just to show you guys what this thing can still do (I might do a video and upload it to youtube, maybe it's easier to explain).
Well let me start then, this thing turned out to be better than I thought, if you search for Pentium 4 in the internet people will say that it is a world of misery and is the slowest thing you will actually find, of course that if you are using a IDE hard drive and 512mb of ram thats true, but if you use a regular sata 7200 rpm drive and 2gb of ram, things just get so much smoother, I mean, you wouldn't say it's the same computer.
As for the GPU, well, I kinda went overkill here, there's no need for 512mb of video memory and there's no need for a gpu like the X1950pro, it's kinda overkill, for instance, I do notice that there's a bottleneck in almost every game I try, here are some games I tried:
(all these games were running on Steam and were played while connected to the internet):
-CS:GO was the first game I tried, it's one of my favorite games right now and I couldn't go without trying it out on the P4, so the pentium 4 is able to keep fps over 40 most of the time playing 5v5 competitive on Dust 2, it really doesn't get past 60fps, but hey, having a machine like this playing CS:GO at 50fps ost of the time is really not bad, but like I said before, you can tell the you don't get more fps because of the cpu.
-GTA IV well this game I remember me playing it some years ago on my core 2 duo laptop with a nvidia g103m, one of the worst gpu you could have at the time, and the laptop couldn't handle the game, it probabily ran the game at about 12-15fps, but I didn't even care, the game was amazing and me and everyone played it even with these fps, so I was surprised that the pentium 4 actually can keep frames over 20fps, like 22 most of the time, which is really not bad at all (both the laptop and the P4 had the game playing with the lowest settings)
-Left 4 Dead 2 nothing to say here, frame rates preety much always over 30fps, only when a lot is going on it drops to 25fps, but nothing much noticable.
-Counter Strike 1.6 frames rates between 200-300fps on dust 2 with lobby of 30 people
-Counter strike source kinda disapointed me, CS:S runs almost as good as CS:GO which is strange, frames rates over 30, but 40 is the maximum.
Well now for web browsing, I'm using WIndows XP SP3 fully updated with Avast anti-virus and I gotta say that only on the heaviest web sites you notice it slowing down a bit, more other than that it's completly smooth, also youtube plays fine, on 360p/480p processor is at 20% of usage, only when you put it on 720p it strugles, but still plays fine with cpu around 70%.
Before I end, I did change the Pentium 4 I originally have, I had a 3.0ghz northwood pentium 4 overclocked to 3.6ghz but then my uncle gave me some old motherboard he had and one of them had a 3.0ghz prescott pentium 4, so I changed it and overclocked it, the prescott overclocks much better than the northwood, I'm able to have it running at 3.9ghz no problem, but for that the ram as to run at 180mhz, and I rather have the ram running at 200mhz and the cpu at 3.75ghz, some of you will disagree but I did notice a imrpovement using the prescott, it feels smoother over all.
But here I must say, I would only recommend you building a computer like this if it is just for fun, the parts cost me:
-Asus p4p800e deluxe with pentium 4 and zalman cooler: 15€ shipped
-x1950pro: 25€ shipped
-4x512mb ram: 25€ shipped
-PSU: 25€ shipped
-Case: 32€
-HDD: 20€ shipped
Total: 142€
Alright, I did get a good deal on the motherboard cpu and zalman cooler, because on eBay the mobo goes for around 20-30€ if your'e lucky to even find one, the cpu goes for 15€ and cooler probabily another 10€ at least, so that would make the price jump quite a bit.
Why this is not worth it? because you can buy a fully working core 2 duo for around 80€ that simply is 10x faster than this.
So there you go, if you guys want me to upload a video showcasing the Pentium 4 I can do so.