I would not mind updating my CPU and motherboard combo . My current AMD xp2400 does everything else that I need it to (ie non-Fsim) and I dont need anything faster for those non-FS things. I do not play any other games.Currently I can buy a single core AMD Athon64 3800 for $165AUD, a dual core AMD Athlon64x2 4600 for $349AUD , or the Intel Core 2 Duo Processor E6600 for $469. You can see that there is quite a cost differential between the single core AMD and the dual cores form both AMD and Intel. I am not really worried about that - but what is the best processor for FSx or FS2004? I have heard some people saying that the dual cores have been a problem with FSx and FS2004. The Intel 6600 is getting really good benchmarks in all programmes - except that FS9 or FSx is never tested with it.Any help much appreciatedThanks Barry

Best CPU for FSX for the money, is the Core2 duo 6700. While I am an AMD fan, it smokes anything AMD has out now.Regards, MichaelKDFW

Asus A8N32-SLI Deluxe nForce4 SLI-x16 / AMD

As still reported FSX may benefit maximum 20% of the second Core performance with reducing the Performance of the first Core for 5% up to 10%. So you'll get maximum 110% of a Singlecore as same Performance per Core. Reducement is reasoned by waiting of both Cores to sysncronize parallel executed Tasks.So think about a realistic comperation between both Architectures.I.E. an Athlon64 4000 Single-core may run FSX much faster than a Intel Dualcore System with 2x2800 MHz (w/o preferring one of both CPU-Manufacturers)The only Benefit of a Dualcore in this Relation may be that the OS and other parallel executed Applications remain with much higher Performance but this also will cost more Memory - and FSX needs minimum 1GB for optimal Execution.Regards Heinz-Werner

The best cpu for FSX right now would be an Intel Core 2 Duo (extreme model, E6700 or whatever it's called).If I were building a new system, I wouldn't even consider any other cpu right now. Even though FSX at present makes only small use of the 2nd core, one core of a Core2Duo is still faster than an FX57, which is the fastest AMD single core cpu.If money is an object then you will have a tougher choice.Best budget cpu for FSX is certainly an AMD 4000+, if you can still find them for the Socket 939. But I wouldn't build a Socket 939 if I were building new.I think AMD makes an FX55 cpu for the AM2 platform, and that would not be as budget, but it's about the fastest single core I can think of. The 3800+ is AMD's new single-core for the AM2 socket. It would probably be a decent budget choice, but I have zero experience with those. If it's anything like a San Diego core (3700+, 4000+, FX57) then it will be a good FSX cpu if you're on a budget.AMD's fast single cores smoke FSX, I can tell you from personal experience. My 3700+ does better than many peoples 4800+ systems...all for USD$100.Really though overall, you would be wise to go Core2Duo if you are building right now.RhettAMD 3700+ (@2.5 ghz), eVGA 7800GT 256 (94.47), ASUS A8N-E, PC Power 510 SLI, 2 GB Corsair XMS 3-3-3-8, WD 250 gig 7200 rpm SATA2, CoolerMaster Praetorian