Any worthwhile pc upgrades?

[saitrix]

I currently have got an aging system and I have started playing Flight Sim X which seems to be pushing my system really quite hard. Is there any worthwhile upgrades for me to do to my pc or is it a case of a whole new pc?

C2D E7200 @ 3ghz (undervolted so don't want to overclock further)
4gb ddr2 800
Ati 4850
1tb Samsung F3 Hdd
19" Hanns-G (1440x900, so not a massive res)
Win 7 64bit

Now I really like a quiet pc so I ideally don't want to start pumping too much more heat into the case, so that might be an issue.

Is there a way for me to work out what the bottleneck is, whether it is the cpu or gpu. I have a friend with a Q6600 G0 he is selling but they seem to go for large money for their performance, plus I don't think I want a cpu that power hungry. I don't play games too much these days but I do like to have a good enough system when I do.

 

[stulid]

FSX eats CPU and loves Vram and nvidia GPU.

Going to a quad core CPU is actually a wise idea, add a card such as a GTX560 etc depending on budget and you will breath some new life into the system.

What PSU do you have?

 

[saitrix]

I am fine for psu, I use a Nexus Value 430W, which my current setup uses 170W at full load so not even getting to the fully efficient power usage on the psu.

Problem is, how well does the Q6600 G0 undervolt? Last thing I want to do is have to increase my cpu fan speed above its 800rpm, let alone above 1000rpm.

 

[stulid]

I dont know how well they undervolt.