Hello people and Season's Greeting!I built my system a year ago; was not able to overclock pretty high wihtout errors (i finally found a failing OCZ memory stick 2 weeks ago) so i bought Corsair 3x2gb 1600mhz kit and re-tried overclocking up to stable 4.0 with 12 hrs of Prime :Applause: Started FSX hoping to see a nice improvment :Praying: It did, WHEN it passed the plane selection screen wihtout crashing.....Always a .dll but never the same, sometimes ntd.dll, g2d.dll, g3d.dll etc...A sure way to crash FSX was using either the JustFlight A-319 (from CYUL to KLAS would crash after 90 minutes) or Flight1 Mustang over any PNW or NA Blue from Orbx, invariably crash wihtin 20 minutes :Confused: Tried a lot of overclocking configurations, lower cpu ratios, lower memory timings etc. Only when on stock 2.8mhz and stock Asus bios settings that i can complete a flight with the Mustang from CYVR heading east for more than 2 hours straight wihtout crashing;Could it be Windows being corrupt from too many BSOD in the last year ?Thanks for your suggestionsAlain from Montreal

If it's only when OC'ing, then I'd suggest it's the OC, not Windows, causing the issue. Random dll failures is typical of instability. Are you running enough cooling? A decent heat sink can make a world of difference to the stability of an OC.

Paul, running Prime for almost 12hrs the cpu was between 44-45 celsius never went above 47 and northbridge 52-53 celsius, that was at 4.0 mhz @ 1.3375v for the cpu, QPI-Dram voltage @ 1.2650 and 1600 mhz/ 7-8-7-20-88-2n @ 1.65v for memory timings.How can this overclock stands Prime for so long and fail wihtin 90 minutes in FSX ?Alain from Montreal

It's certainly possible for an OC to pass on synthetic testing like Prime95 but then fail in real world gaming applications - I've seen it before myself.What are you using to measure your temps and what are you using for cooling? 44-45C seems *incredibly* low for a 4GHz OC under full load. Make sure you're using CoreTemp or RealTemp and not anything that only accesses the motherboard's sensor. My temps in Prime are low to mid 70s at 4GHz and a 920 should run hotter than my 860. I'd consider increasing your Vcore voltage too - 1.32 sounds low to me for a 920, they usually require more voltage than an 8xx does and I'm at 1.35v on mine.

I use FSX as my stress test, as I too have seeing the same thing. Run prime 95 for 10 min and FSX whcill crash in 2. So if I can managae a 1hr flight in FSX then it usually means everything is ok.

Hi Alain,Like Ryan said, such a low temp at 4ghz indicates too low voltage as voltage is what causes the heat. If 4ghz is the high end of your cpu speed then your voltage will probably need to be near the high end maximum for that chip.Anti-viruses love to screw your dlls also, look into that.I hate to say it, but after running a failing memory module for so long, it would be a really good idea to spend a couple of days reinstalling your system from scratch :Nail Biting: David.

Ryan makes a really good point. My 4.0ghz 930 idles at 40 or so (and here in the UK we're heading towards absolute zero, in ambient temps!), so under load 44 looks way off base.I'd still avoid the re-install, though I sympathise with David's point, till I tried the voltage/heat fix. I still think that, if your install was screwy, you'd see that when running stock; the fact that you only get it when OC is pretty conclusive, for me.Good luck :)

Maybe he got high end water or water + TEC or something. I do know that alot of 920s doesnt actually need 1.3 to reach ~4.2ghz. I have seen ridic numbers like 1.22 for 4ghz (xeon w3520, not i7 920, but its the same chip, different branding). It varies alot from batch to batch, and even from chip to chip in the same batch.

Thank you everybody for answering I am using a Coolermaster cpu cooler similar to a V6, in a Coolermaster CM690 nVidia edition case with 6 120mm fans plus an Antec Spot fan aimed at the northbridge...It's loud but efficient :Big Grin: The temperatures are monitor by a lcd poster that reads the same values as inside the bios so i suppose accurately?When playing FSX on heavy scenery like ORBX, the cpu temp reads between 47 and 50 degrees and the northbridge @ 57...I based my voltage and different settings from people on overclocking forums with the same material, altough i agree FSX can be more taxing than other software...I am leaving for a 2 weeks vacation tonight so i will not be able to try anything till then, i''ll keep you all posted ! B) Alain from Montreal

Thank you everybody for answering I am using a Coolermaster cpu cooler similar to a V6, in a Coolermaster CM690 nVidia edition case with 6 120mm fans plus an Antec Spot fan aimed at the northbridge...It's loud but efficient :Big Grin: The temperatures are monitor by a lcd poster that reads the same values as inside the bios so i suppose accurately?When playing FSX on heavy scenery like ORBX, the cpu temp reads between 47 and 50 degrees and the northbridge @ 57...I based my voltage and different settings from people on overclocking forums with the same material, altough i agree FSX can be more taxing than other software...I am leaving for a 2 weeks vacation tonight so i will not be able to try anything till then, i''ll keep you all posted ! B) Alain from Montreal

Don't use whatever temp monitor came with the mobo - that's not giving you the actual core CPU temps that are reported from the chip itself.Download and install CoreTemp and monitor with that when running Prime95 - I bet you'll see much higher temps. Those Coolermaster V series heatsinks aren't that great, there's no way your load temp is actually 44C. What those motherboard apps read is the sensor on the board itself located below where the CPU sits - that's a much cooler spot that right inside the chip cores themselves.

In addition to Ryan's suggestions, use OCCT as your stresser for the clock rather than Prime. It provides a better test against what you get with FSX than Prime95. Run it for an hour and then try FSX. Still, I have seen clocks pass the stressers and fail in FSX many times so if FSX crashes - adjust your clock.

Hello all,You guys were right, with Coretemp the readings were much higher than on my LCD poster...So i decide to go water cooling, found Corsair new H70 system, very easy to install and super efficient, 36-37 degrees Celsius @ idle, 54-56 under heavy load in FSX, O/C tested with OCCT ok, prime95 for 12 hours OK :Applause: I also completely re-install Windows 7 64 and FSX so i can hopefully say after a week of testing that my problems are behind me for now :Nail Biting: Thank you all for posting !Alain from Montreal

Hi all,Good to hear that your problems have been fixed. I Read a while ago that FSX should be installed AFTER OCing because OCing with FSX already installed causes corruption in certain files (in your case DLL's). I think it should be made a note to all that OCing should be done before FSX and addon installation.

Hello Alex; Any specific explanation why we should overclock before installing FSX to avoid corrupting DLL ? i read a post from NickN that overclocking should be last, when you're sure FSX works well ? thanksAlain from Montreal

yeah it makes no difference to the .DLL that's just silly. Although I do believe your cpu clock is used for initial slider settings.