I am in the process of putting together an order for a new system and have sorted more or less everything except the procesor. The reason being is because I just cannot make up my mind which is the better option.My initial feelings were to go for an Athlon 64 X2 3800+ (Skt939) as they represent such good value and I hear the Manchester core can easily be clocked up to 2.5GHz. Then I thought perhaps an X2 4400+ with double the cache may be a better option. I understand AMD are in the process of switching to AM2 (Skt940) processors and with it from DDR to DDR2 memory. Therefore I wondered whether a similarly priced Athlon X2 3800+ would be a better option in Skt 940 than 939 given the faster RAM and new Nforce motherboard chipsets. However I also heard that DDR2 memory latency can be a problem at certain multiplier settings (i.e. odd numbers 9x, 11x etc, etc).A further option would be an Intel core duo. I know the higher cache would be an advantage but I don't know how they really compare in terms of FS9 performance for example.The problem with review websites for me is that I do not use the software they happen to test the hardware with (i.e UT, Far Cry, Doom 3, Half Life, Quake 4 etc) therefore the results mean little to me. What I do use a PC for is Flight Simulator 2002 & 2004 and intend to add FSX to the list as and when. I also run Microsoft Train Sim and do a heck of a lot of multi tasking too (often 10 or more applications running simultaneously on desktop) as well as lots of large download files in the background too.Which would be the best all round value CPU for overclocking, FS9 and mulkti-tasking?....and, would I require any specialist cooling equipment to overclock by around 30-50% (eg Athlon 64 X2 3800 from 2.0GHz to 2.5GHz or 4400 X2 from 2.2GHx to 2.75GHz)?

A further query I have is that of motherboard brands. I hear Asus boards are not the best for overclocking, whereas I hear that ABit and MSI boards are better. Any first hand experience/knowledge would be much appreciated.

OK..First off..This is all gonna be stuff I've read or "heard" from folks I consider stright-up..there may be a bit of my own opinion mixed in there..The reason I mention that is I'm kinda big on only talking about what I have personal expierence with...I really think some more "overclock specific" reserch would benifit you..I'm kinda new to overclocking myself...I have some limited expierence with it thusfar..I have done some reading..And since no one else has chimed in here I thought I would..I "Hear" the new Intel Core 2 Duo and the Core 2 Extreme's are suppose to be some really good overclockers...I'm not sure how much reading you have done on them?? But the info that is out there now is going to be more in the form of reviews rather than personal reports as they are not widely avaliable in the USA at the moment...There is not much of a motherboard selection avaliable just yet either...I'd personally like to hear some "Personal Feedback" when the nVidia 590 equipped motherboards become avaliable...They will get here...It's just going to be a while...I'm not aware of much feedback pertaining to FS running on a Core 2 Duo system...Like you mention...All of the Benchmarks I've read(one exception) are using other software which I'm not interested in either..Sim Outhouse did post a little Data on FS9 running on a Core 2 Extreme system...However..Much like you...I'm gonna take that with a grain of salt...I wanna hear how Core 2 Duo run's with some Aircraft, Scenery, Traffic and other typical add on's...To my knowledge that info just isn't out there yet??The AMD Socket 939 design is still around and is a more refined platform than socket AM2...By "More Refined" I mean..AMD has the 939's Memory Controllers dialed in...The AM2 platform is "apparently" not quite as efficient with the DDR2 memory..Therefore there is not allot of performance difference between socket 939 vs AM2/DDR2 set-up...That is one reason I have decided not to swap my 939 stuff for AM2/DDR2 just yet...There would be no real performance gain from doing so...I've elected to wait things out...However...If I were putting together a new AMD based system today...It would be socket AM2 for sure...Your statement reguarding LvL2 cache: LvL2 cache has become a term we all are aware of...The common thought is "More is Better"..I have always agreed with that..However..I have recently learned that AMD's processor design does not require the large amounts of LvL2 cache from an efficiency standpoint...(I do not claim to understand the engineering aspects of processor design!!)...But apparently Intel's performance is based primarily on the Large amounts of LvL2 cache...AMD's performance is not...Their performance comes from the design of their onboard Memory Controller...Large LvL2 cache is apparently not necessary with the AMD processors...In fact AMD is phasing out all of their mainstream processors which utilize 1mb of LvL2 cache with the exception of their FX Processors... I just purchased my first x2 processor...I plan to overclock it also...I have a 4000+(single core) processor which I have had running at 2.8ghz for a good while...I took that system apart to stick the 4800x2 in...I kinda wanted to get a direct comparison between single vs dual core performance...I also removed my DangerDen Liquid Cooling system while making this swap...I will put the 4000+ back in there and resume the OC but this time on air...I feel can get that moderate OC on air with no problem...I have enough spare parts laying around to build the 4800x2 up also...It's going to be aircooled as well...I hear that I may not get 2.8 on the 4800x2?? Not sure where I read that anymore...An Asus forum I think...2.7 or 2.75 may be about all it will do?? not sure yet...I'm hoping for 2.8...Cooling is the key...I'm sure your aware of this and have cooling solutions in mind...I'm of the opinion the higher quality air CPU coolers come close to liquid cooling these days...Unless your going to invest Allot in a liquid system..I feel you can get some semi strong overclocks on air...If you plan to get pretty radical..I'd look at a Phase Change Cooling set-up...I see one of those in my future..he heTaking my 4000+ from the stock 2.4 to 2.8 was pretty easy...FS9 responded nicly to the overclock as well...Not a whopping improvement...But you could tell it liked it...The sim is smooth at 2.4...I feel at 2.8 it's smoother and slightly more responsive...I doubt I helped with much insight to any of your decisions...Sorry to Ramble...It looks like your reading up on the processors your considering...That is good...Spend some time checking out OC'ing forums...Kinda like reading reviews..You'll have to weed out the stuff that really doesn't pertain to you...But there is allot to learn out there...I'm at the same point myself... Since I don't have any expierence with the 3800 or 4400 I'm not going to say anything..It sounds like you've investigated them a bit...I'm also not familiar with the neuances of overclocking with DDR2...As far as Motherboard selection...I really like my Asus stuff...I will handle my Moderate overclocking...However I do believe allot of the hardcore guys do shy away from them...I've also heard DFI boards are popular in the OC'ing arena......I like the Asus stuff as it's nice and stable..Easy for me to tinker around with some moderate OC's...If I find I want to really get more agressive I'll probably swap also...Gonna have to reserch when that time comes myself...Good Luck with your decisions...Have Fun!!

Chuck....Great to meet you. So sorry it has taken me thus long to reply to your post.Thanks so much for taking the time to go through everything with me. I found it all very insightful. In fact i've actually taken it on board too....Believe it or not I have decided on an Intel Conroe E6700 2.67GHz CPU w/4MB L2 Cache! You are right with regards to their O/C capabilities. The only problem I had initially in choosing Conroe was the additional cost over the AMD AM2 and also that of the very limited SLi/Crossfire motherboard chipset support. However, I have found a great set up and a good price too. I still have to decide on a GPU card, that's the hardest part, but the system itself will be here in less than 3 weeks. Here's the spec:Intel Core 2 Duo E6700 CPU @ 2.67GHz 4MB L2 cache!Asus P5W DH Deluxe Motherboard (Intel P975 chip) 1066MHzMaxtor 250GB SATA II HDD @7200PRM 16MB buffer cache2GB Corsair DDR II RAM 800MHzThermaltake Soprano Black case, 6x USB2.0, 2x case fans550W PSu Dual rail2 x 120mm fans21" monitor & Geofrce or Radeon GPU to follow.Not sure what to do about GPU with DirectX 10, Nvidia G80 and Vista just around the corner.I have in mind to gradually upgrade cooling as the need to overclock arises. I wouldn't imagine I would get much initial benefit in FS9 by overclocking a CPU that already beats an Athlon FX62 hands down. The new cores are amazing. However, I am looking ahead to when the time comes to raise the FSB speed onboard. Perhaps with FSX I may see a better yield from mild overclocking. In any case I doubt I would want to take the CPU past 3.2GHz. Would be afraid of frying something...LOL! Can't wait to try it all out. I have lived uncomfortably with my Athlon 2200XP & Geforce 4200Ti for too long. Flying will no longer be a slide show!Pleasure to talk to you!Scratch1964