Hey guys,
since my grandpa's Parkinson got worse and he decided to sell his car and give the money to his oldest grandson (guess who, woot) I was thinking about upgrading my computer. I find myself turning more and more to the PC versions of the new games (well, at least the ones that are actually port, not almost direct console ports like ME2).
Right now I have a Athlon 64 X2 6400+ (I don't remember the socket, it was either 939 or AM2, I recall that it was the fastest CPU for that socket at the time of purchase), 4 gigs of DDR2 RAM (667) and a Radeon 4870HD 512MB.
It's not bad, I managed to run SC2 on very high, Mafia 2 demo runs with almost everything turned on, DA:O ran well too. There's two issues though.
The GPU lacks a HDMI port. I was thinking of getting a wireless PC pad, connecting the sound card with the home theater system and plugging the HDMI directly to my TV. That way I could play my games comfortably from the couch, with all the PC bells and whistles, big screen and a 5.1 sound. Plus, I wouldn't have to use the sloppy streaming for my HD movies and instead I could just display them directly on the TV.
The other issue is that the rig has some really ancient components. That's because it was bought over four years ago and later on upgraded a bit. I had a Athlon 4200+ and the 1900XT Radeon. That means the MoBo is old, with old socket that's already using it's fastest CPU possible. RAMs are nothing special either, being 667. I also replaced a PSU because my previous Tagan simply exploded in front of my eyes (sic). Also a Sound Blaster Audigy 4, lol.
So, to cut the crap short. I was thinking of replacing a MoBo to something i7 ready and getting these:
http://www.gainward.com/main/vgapro.php?id=394
http://ark.intel.com/Product.aspx?id=41316
and replacing RAMs possibly to 6 or 8 gigs DDR3 1333 or higher.
So my question is: IS IT WORTH IT? These four components themselves will cost around 1000$ so that's a lot but I am willing to go for it IF it's worth the price. What do you guys think? I was also thinking about upgrading the GPU alone for the HDMI and stuff but that would leave me with the dumb bottleneck MoBo and CPU.
I'd be super grateful for any advice you can give, thanks!

You might be better off going for a more general test. Open your case up, point a fan at your computer's innards, then run the applications that were causing it to crash and see if the problem still occurs. If it does then it's probably not an overheating problem, while if the application is suddenly stable then it is due to something overheating. If this test does point you to overheating then go for a general solution first, such as cleaning out the filters on the case's air inlets and rearranging the wires in the case to allow for better airflow (these two simple things can actually have pretty remarkable effects on overall temperatures).

Like others said you should wait. My system is 4 years old but it was a beast at the time. It still runs most games decent with everything on high (including metro 2033) and mafia 2 demo even had a playable framerate. but that's the problem: decent and playable =/ perfect. But i can always turn down the graphic settings and stuff so when i still can play most of them without much problems and quality trade off i think i shouldn't replace my pc. Frankly i'm scared to death to buy me an expensive pc now only to find out it struggle to run my most anticipated game next september (RAGE). (offtopic: Duke nukem forever is my most anticipated game ever but if it ever comes out I doupt you need a top of the line pc ;) )

DarrkPhoenix's suggestion about the fan is a good diagnostic step. If the computer shuts down (are there any lights or fans still running?) rather than bluescreens, it implies a safety cutoff from either heat or power. It is also possible that you're drawing too much current from the wall socket, when I'm playing DoW2 and the screen is full of explosions and ork parts, the UPS I have my gaming rig plugged into gives the annoying low battery beep so high intensity gaming does draw a lot more power.
If it is a heat issue then based on my experience, its likely the CPU. GPU overheats tend to corrupt the display and lock up rather than shut the system down. It might be worth pulling the CPU heatsink off, giving it & the CPU a good clean with isopropyl and a fresh bit of quality thermal paste, especially if you had a thermal pad on the heatsink to begin with, those go crap over time.
As for the upgrade, it might be worth replacing the core components but keeping the current video card if that seems to handle most things well. That way you can upgrade the GPU seperately when the current card loses its effectiveness (or when the next shiny chip revision comes out) and a socket 1366 motherboard would stay useful for a long time so you could probably upgrade the CPU later as well

I think now or in about six months is a great time to upgrade, personally. AMD has its cheap six core CPU, and there are some really good value for money offerings from ATI and NVIDIA, with new stuff on both fronts looming on the horizon. RAM is not so cheap, though...

You know, the problem is that it only happens while playing Dawn of War 2 so I'm guessing it has something to do with the Essence engine. I've been playing games like DA:O, Crysis:Warhead of Civ 4 for 6 to 8 hours straight and nothing happened. The only other issue I experienced was the Radeon's driver BSODs I talked about earlier. That's why it's so strange.
I want a Intel/nVidia combination this time. Call me strange but I have an old habit to shift the manufacturer every time I do a significant change to my rig. So this one is AMD/Radeon (or more like AMD/AMD, lol), previous one had a GeForce 6600GT and P4, then before it AMD/Radeon and so on. It's just a weird thing of my brain :P

I'm stunned you looked for an example of a poor console port and picked Mass Effect 2. That was a great port.

No, no. I meant that compared to, say DA:O, there are not that many significant differences in graphics between PC and X360. I didn't say it's a bad port.

Oh, okay.
Yes, I suppose it just has the usual resolution/AA/AF enhancements. Plus mouse aim. Dragon Age was like a whole other game. So I take your meaning.

Does anyone know a good website where I could compare benchmark results of various GPUs? Thanks!

Toms hardware give side by side benchmarks of all current VGA cards, they also have a handy buyers guide for different budgets.

Mass Effect 2's graphics can be improved as follows:
-rename executable to ut3.exe, force higher AA in control panel
-add trilinear=true to gamersettings.ini
-disable film grain
Voila.