guh vexer, you've made me want to build a new PC even more...sadly all my money right now is devoted to education and bills...
Also regarding processors...Intel and AMD seem to have completely different philosophies on how to make faster computers. one feels you must crank to core clock speed (Intel) and the other prefers an even balance of high clock speed and good FSB multipliers. (AMD)....In my experience, and I've built A LOT of computers, used to do it for a living, The AMD route is better. It produces a faster computer over all.
As for over clocking, while it's great while you do it, in the long run your processor will be slower sooner as the diodes will bias faster.
If you're going to be using general productivity tools or any development, I highly recommend going with dual monitors. Having your reference material up along with your IDE rocks. The drawback is that a multi-head video board good enough for gaming will cost you.
While you're at it, grab a couple hard disks and removable trays for them. Put a backup strategy in place and use it.
Additionally, your budget is too high. Some time ago I built a machine for around that amount. My goal was silly--it took the experience to realize it. Don't build one end-all desktop with maximum expandability, the latest peripherals, etc.. I have a machine that takes up too much space, cost more than what I needed, a power supply that supports more than I've ever plugged into it, a UPS that just ended up failing anyway, and it still became out of date in the same time frame.
If I could go back, I would buy one with space in mind. Spend the saved money on some good books.
Hardly lower-end, it's mid-range at the least. If it can play Crysis, I don't consider it low-end. And these things generated a fair amount of heat, they got to 100C once. Now they cap with my CPU at ~70C, but only with FurMark running and Prime95 taking up 3 cores.
I agree with moorecm. Don't buy thinking about future expansion, expect maybe on the HDD department. What you don't buy the first day, you're not going to buy.
NGen: What CPU are you using? Sound like it has a bit of a cooling problem. Mine is a Core 2 Duo and it rarely reaches 40° C even on sustained full load. And my case has the worst possible air flow. I bought the cheapest case I could find that would fit my motherboard.
AMD Phenom II X4 945, water cooled in the same loop as both of my 100C GPUs. While I was hooking it up I was wondering if it was worth putting both GPUs on there since it'd mostly serve to just add more heat to the liquid. I really just need a better radiator, my current one just has a single fan on it.
I've read a lot about the just-released GTX 460 card. ~$200 a pop and when you put two in SLI, they either match or beat the performance of two $500 Radeon HD 5870s. Don't quote me on that one, but I just know that they scale amazingly well in SLI. So I obviously suggest that card since it's still fairly good on it's own.
If your CPU is getting over 60C then you need to fix your cooling. For GPUs it's not such a problem - mine regularly gets to ~91C when playing GTAIV. I think GPUs can survive past 120C so 100C isn't THAT bad. I'd still recommend better cooling, especially for your CPU.
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How does the GTX 460 compare to the GTX 260? What about the GTX 295?
Edit: In retrospect I probably should have checked.
Also why would you use google.com instead of google.es?
Edit 2: The laugh overed quickly, though, because I accidentally refreshed my "Edit document" tab, in which I was editing my compilers and IDEs article, and lost my work.
Damnit. Probably I should use a text editor instead.