Could really use some advice (fans/cases/gfx card)

[Lachan]

I bought my PC 2 years ago, has been working great (runs a bit hot, but has never really been a problem), the only intensive stuff I ever use it for is gaming, however recently my graphics card will occasionally overheat to the point that it causes my PC to crash (monitor acts as though PC is off, can still talk via ventrilo for a few seconds, then PC shuts down). I've always kept everything fairly clean, but just to be sure I cleaned out everything really well to be sure it wasnt dust causing excess heat, but the problem persists.

So I think I should either get a new graphics card, a new case with good airflow, an aftermarket gpu cooler, aftermarket case fan...or all 4...
however I know next to nothing about parts, what to use with my hardware, how to check whats works with what, I could attempt to figure it out myself, but my budget isnt large, my computer was expensive and I dont want to screw anything up or waste a buncha money because I bought stuff that wont work

Now wall of text aside these are my specs:
Studio XPS 435MT
BIOS: 1.0.12
CPU: intel core i7 920
Motherboard: Dell 0R849J
Graphics card : Radeon HD 4850
RAM: 4096MB DDR3

I also attached a CPUz report thing...
oh yeah, according to MSI afterburner my gfx card runs at ~75C when I'm just browsing the internet (so all I've been doing since I turned computer on)
When I'm playing Aion (mmorpg) with lowest possible graphics settings temps seem to be between 95C when I'm idle for a long period of time, to 110-115C when I'm actually playing

Any advice/suggestions would be very much appreciated.

 

[FuryRosewood]

...or you could just dust the case out and see how that goes, ground yourself out, take the case outside and lock the fans with something, and hit it with compressed air to break the dust out of the heatsinks, then see if things improve. I dont think its a case airflow problem as much as a cleaning that is simply needed, with high watt systems you typically have to keep on top of this

 

[Lachan]

...or you could just dust the case out and see how that goes, ground yourself out, take the case outside and lock the fans with something, and hit it with compressed air to break the dust out of the heatsinks, then see if things improve. I dont think its a case airflow problem as much as a cleaning that is simply needed, with high watt systems you typically have to keep on top of this

So I really don't wanna be rude, especially when I'm asking for help, but I wouldn't be asking for help if it was some stupid easy problem like cleaning my system out, if you read my post you'd see that I've already done that.

I've always kept everything fairly clean, but just to be sure I cleaned out everything really well to be sure it wasnt dust causing excess heat, but the problem persists.

 

[FuryRosewood]

Okay then. Well first thing i can mention with your dell, your front panel connection will possibly be custom, tho i think dell has gotten better about that, any cheap case may do well, lian li makes a good mini tower with the PSU mounted up front that works relatively well as long as your not running it in a HOT environment... keep in mind HUGE case doesnt necessarily mean good case, just have to have good cable management so air flows smoothly.

http://www.newegg.com/Product/Product.aspx?Item=N82E16811112218

-running with a W3550 with 12 gig ram, stock cooling, GTX570 and a HX Corsair PSU, and it is stable unless the room gets rather warm, around 80F or greater, or your at 8000Ft up...