Hello HW gurus out there.I have following dilemma : go SLI or get a new processor.First my system : Processor : Intel E6700 @ stock speed 2.66GHz Memory : 3 GB @ 667 mainboard : P5NSLI from ASUS Videocard : Nvidia 8800GTS 640MB HD : 2x500 GB not in RAID (FSX and OS each on its own HD) flatscreen : resolution 1680x1050 sound : soundblaster XF-I Xtreme Audio OS : Vista x64I am well aware that the more pixels you have, the more work and the more memory you need. Especially if one wants Anti Alliassing.So where would the bottleneck be in my system (don't tell me Vista :-) ) ?I tested DX10 in Acceleration, and I am happy with it (bloom on all the time and water settings at high).I was thinking about getting a second 8800GTS 640MB, or wait a bit and get a faster processor at the end of the year.Anyone running FSX in SLI with DX10 ? What is your feeling when you go higher in screen resolution ? Or will the processor (as in the past) be the most important ? Or do I need new memory ? Difficult choice. And I only have so much money to spent.Jan

Easy choice, SLI does not help FSX, a faster processor speed will directly increase frame rate.Save your money. Use DX9 with Vancouver + suggested settings.If you want to add a few frames per second you dont even need a new processor, just read about overclocking yours. Most 6700s hit 3 - 3.2 GHz rather easy. Thats about a 20% increase for free!

Yes, think about overclocking. By the time the CPU breaks down (OC reduces lifetime), get another one, they'll be cheaper then, or get a successor (Penryn, ...) that'll be higher clocked by then or could be overclocked more ...At least OCing helps you finding out if CPU is the bottleneck.SLI: Usually no help in FS, SLI brings in own problems. SLI for DX10: unknown, somebody should test. And maybe that is Jan in this case?Please don't forget some screenshots with fps ... ;-)Bigean

I did try overclocking, but I get CTD after 5 to 10 minutes.Sometimes I do not even get past the loading screen.I am convinced now that I did some bad choices when building this system : the mainboard (nvidia nForce4) and slow memory (667Mhz).But I was wondering if anyone else tried SLI with FSX DX10 before digging up the money in my backyard.jan

I would first off get faster RAM. You should be shopping for at LEAST PC6400 (800MHz) or PC8000 (1066MHz) ram. That old 667 just won't cut it. Why you're getting CTD with the overclock is most likely the motherboard or ram. With that processor not being an extreme, the multiplier is locked at 9, so the only way to incerease it's speed it to increase the system bus speed which will also overclock your motherboard and ram (unless you can unlink your ram, but only high end boards usually have that.) If you can, leave the overclock and return your ram to stock speeds and try that. On water I've had my MB (stock 1066 fsb) up to 1440MHz so far, with the proc (2.4 stock) at 3.24 stable all day long at 25*C. My NB rarely goes past 40*C.

Unless you don't have enough heating in your room, absolutely forget SLI for FSX @ 1680x1050.Re your overclocking attempts, your mobo and CPU should be well and truly capable of 3.2GHz+ operation, but your memory @ 667MHz is likely holding you back if it is scaling up directly with your overclock. See if you can force your mobo to run the RAM at DDR2-533 speed or manually set the RAM speed on the Advanced-Frequency Control-New Mem Speed to a target memory speed of less than 667MHz with your overclock. Also make sure your PCI-E bus is held at 100MHz.Gary

thanks,I indeed suspect my motherboard.I checked the manual, and it supports following memory :- DDR2 with 667 MHz capability- DDR2 with 533 MHz capabilityBut in Bios is marked that I can use 800 MHz (checked while overclocking).So I am afraid I will need to change the MB as well if I want to go to 1066 MHz ? What would you suggest ?I already did what you suggested, but still get CTD. Processor is running fine otherwise at 3.3 GHz, and this without additional cooling (not heating at all, I use ASUS AI booster to monitor).Jan

ok, I tried your tip : I forced my RAM speeds manually to 533MHz. Now I can overclock my motherboard to 3GHz. Anything more results in a lockup during boot. But at these speeds, the system is running stable, and not overheating at all (50

Exactly. Higher speed memory is your ticket to higher overclocks. I actually googled your motherboard and many are running memory DDR-800 and higher with great success.Gary