You can find the Newcastle's at www.newegg.com. I just ordered the 64 3400+ last night for some $233 US. Apparently, the Newcastle is supposed to out phrase the Clawhammer, too. NC is relatively newer, and cheaper to produce.

I researched this as well, as I too am upgrading and was trying to seperate the Fx and the 64. Basically, you can get a 64 that is a little faster to match up with the FX. For example, the Newcastle 64 3400+ 2.4GHz performs at least 98% against FX-51, but at only 20% the price :) You can find this at www.xbitlabs.comAnd I just ordered the NC 3400 last night! I'll write up my upgrade :)

Either way they both run at 2.2GHZ, so it's preference on whether you want the S939 or S754, also the S939 have a 2GHZ FSB instead of a 1.6FSB like the S754, so that makes a difference as well, yes the cache is lower but I doubt the difference will be noticeable, same as with the Dual channel RAM very little difference, but the faster FSB will make a difference.

The difference is notable especially in games :). Not earth shattering but definiatly notable. Do about as much as dual channel sometimes more.

My experience personally as professionally it doesn't matter because nothing is "future proof" it's going fast with the "new hardware"...At the time you are going to upgrade hence the socket or memory and cpu are probably changed...For me just upgraded from XP2600+ with 1 Gb PC2700 to a Asus K8N mobo AMD 64 bit 3400+ and PC3200 low latency timings yep and a 754 it rocks :-) rest of system SATA drive + 9800 Pro and Enermax power supply 430 ok from old system (lucky son of my with his new XP2600+ in our network lol)At the time I will upgrade again (over one year+) it will be a new mobo + mem + cpu at least ;-)Overall the system has to be in balance ;-)As for performance terms the S939 has support for dual memory thus a better bandwith in memory ;-)However what will be the actual difference in frames (maybe 4 fps)... so you can calculate what every increase in framerate will cost :(Succes with your choice either way it will be a very fast system :-)Andr

Thanks AndreCan you expand a little on your comment about the system being in "balance"? How do I make an assessment on the "balance" of my future system? What you say seems to make sense but I would like to understand the "balance" concept because I think that if you understand that - the choice of hardware will become a lot more straightforward.

So the Socket 939 3400+ is clocked the same as the 939 3500+? Maybe it was a missprint somewhere? Or have AMD named their naming scheme?

Regardless of the specs the benchmarks for the 3400 & the 3500 are very similar, the 3500 wins some and the 3400 wins some. I went for the 3400 because in another 2 years or so when I upgrade again I doubt that they will be making chips for 939 boards and where I live in Australia it was about $150 cheaper. But this could well change as I understand that the 3500 with half the cache is cheaper for AMD to produce. Very happy with the performance overall but the PMDG 737NG and other payware aircraft still struggle in some high density 3rd party scenery areas. Hopefully an upgrade from my current nvidia 4800SE video card early next year will help this. Bruce

Hi Mike,You are welcome as for your question...Balance of system...What I mean with balance is make sure you don't have a bottle neck in your system what will slow down your new purchased system...A fast CPU / motherboard / memory / slow VGA / and average hard disk(Result: fast calculating system with great bandwidth but it has to wait for the hard disk or VGA)A slow CPU/ average motherboard / fast memory/ fast VGA / average hard disk(Result: slow calculating system which never will use the fast memory and fast VGA)A system in balance:Fast CPU/motherboard/memory/VGA/hard diskFast CPU/motherboard/midrange memory/midrange VGA/midrange hard disketc...Example:Out balance in case of FS:AMD 64 3400+ /mobo/PC3200 memory/7200rpm, 2Mb, ATA100 hard disk with access time of 9,3 ms/FX5200 Geforce VGA or ATI 9200(Slow VGA and hard disk)In balance in case of FS:AMD64 3200+ / motherboard / PC3200 memory/7200rpm,8Mb,SATA hard disk with access time of 8,2 ms/Geforce 6800LE or ATI 9800 pro Some tips:- For FS CPU power is most important of all.- a quality power supply of minimum 360 watt or higher (depends on your VGA)with the AMD 64.- As for the 754 socket make sure to have the recommended memory with your new motherboard.- Quality cooling system and case.- Reading a lot of tests and benchmarks from different sources.- 1Mb or 512Kb cache on the processor lol in many games the 512Kb cache is faster as the 1Mb.It depends all on your budget and what you are willing to spend...Hope this is of any help to make your decision easier ;-)

Thanks again Andre, Yes that makes perfect sense and helps a lot.What I have noticed most as a result of the very helpful feedback in this thread, is that I am now much more critical when I review the price lists on the suppliers site. Whereas in the past, my eye would usually just scan down the price column first and select the cheapest, I now look much more closely at the specifications first and the price column last.

Yes clock speed is the same. No missprint. As for why that's just how they did it.

Bruce, The 754 socket AMD's are certainly cheaper over the "ditch" here in NZ also - about $NZ100 cheaper, same applies to the mobo. I thought that the 939 socket though was the "future" socket rather than a "sunset" option. However, two years is probably about as far into the future that I am looking.So by staying with 754 socket (i.e. 3400+) the cash saved can be used for better spec'd memory/hard disk/video (achieving better balance - as Andre would say).

Just for the record the 512 kb versions is never ever faster than the 1 mb A64:s if the clock speed is the same and no dual channel :) Only in very rare circumstances the 512 Newcastle cores with dual channel is faster then equally speed Clawhammers.This is not only due to the 1 mb cache but that the Clawhammers (most of them anyway) defaults to 1T command rate for the RAM which really helps performance. More so than the less mem overclock you get with it enabled :)Just to clear up an already clear and excellent post I totally agree upon :)Though faster harddrives I have never seen much benefit of. Helps a bit with loading times before starting the sim but otherwise I haven