After a long deliberation & without knowing much about specifications, out of a hunch I propose to upgrade my box with these below, & braking my long tradition with AMD I went Intel for a change.

Besides daily use of my PC the only game I use is FS9 (not fsx) & the only reason for upgrading is to improve as much as possible my fs9.

I hope an expert will advise as to whether all these components are compatible with each other, or did I choose the wrong bits for that Mobo?.

MOBO:- Asus P5K Premium/WiFi-AP Intel P35 (S775) PCI-E DDR2   £123

CPU:-  Intel Core 2 Quad Pro Q6600 2.40GHz                              £152

RAM:-  Crucial 4GB (2x2GB) DDR2 PC2-5300C5 200-Pin SODIMM Dual Channel Kit  £ 58

Sapphire ATI Radeon HD 4870 512MB GDDR5 TV-Out/Dual DVI/HDMI (PCI-E)       £188

ORrrrrrrrrr  should I go for :
XFX GeForce 9800GTX 512MB DDR3 PCI-E Dual DVI    £174.90

thanx     nick

I'm still using a similar rig to your's and I'm running FSX quite reasonably.

The difference is that I'm overclocked to 2.75ghz and I have a decent graphics card.

My 3700+ has the same stock speed as your cpu, and I have the old  A8N SLI plain vanilla mobo.

You could probably clock up the venice without much trouble and pop the 4870 into it, providing your PSU has the grunt for the 4870, and you won't recognise your present machine.

If you still are not happy, then you can upgrade the whole rig, and you already have the 4870.

I think you'll be amazed at what the 4870 will do, (complete overkill for FS9), but you'll need to get that venice going quicker to match it. If you are just planning to use FS9, then consider a lesser/cheaper graphics card, the 4870 is a power hungry heater.

Back to your upgrade.... cpu core speed is important. E8400's come stock at 3ghz, and they easily clock to 3.4-3.6ghz with little or no added voltage. Ram should be minimum cas4 PC6400 or cas5 PC8500 with low stock volts preferably.

P35 chipset is ok, but there are plenty of later options, including P45, X38 and X48. I've been using the Asus P5Q pro (P45) in a few builds and they are ok, but there are plenty to choose from. The X38-48's are good if you want to Crossfire a couple of G cards, but they are more expensive on the whole.

WD 640gb hdd's are good, fast and cheap.

Edit: Mind you, if FSX is in your future, then there are better options.