Has anyone found a cure for StackHash errors (BEX events)?

 

Does uninstalling and re-installing FSX only do the trick?

 

Iain Smith

When are you getting the BEX/StackHash CTD?  If it is during a flight then it is most likely memory related (you know, high settings, bad overclock, bad memory settings in BIOS).  If it crashes when you close or shutdown FSX, then it might be fixed as the shutdown is the clue (whether in windowed mode or full screen mode).  If I shutdown in full screen mode, I'll get it 100% of the time.  If I shutdown in windowed mode, no crash is shows up.

 

Best regards,

Jim

If it is during a flight then it is most likely memory related (you know, high settings, bad overclock, bad memory settings in BIOS).

 

Hi Jim, it happens during a flight at varying intervals. The other evening I went out leaving a flight running as a test. I came back two hours later and it was still running and by the time I had to shut it down to retire for the night it had done nearly five hours without crashing. This was after I had increased my virtual memory at the suggestion of my son-in-law, an IT professional, so I thought it was fixed. Next day though it was back to normal, crashing after about 30 mins.

 

I've had this Asus P8 Z77-V LX motherboard with an i7/3770k o/c at 4.4GHz, 4GB RAM, Geforce 550Ti 1GB graphics, running with Win 7 64bit since the end of April with no problems until a couple of weeks ago when these crashes suddenly started happening. Memory timing in the BIOS is set to auto and in this warm (for the UK) 86F or 30C weather, CPU temp peaks in the mid 70s when running FSX. I thought I'd tracked it to some Windows updates which I uninstalled but to no avail.

 

I could dial back the o/c to 4.2GHz but I'm lost on setting memory timings. Any advice here please. I don't have scenery or autogen maxed in fact the only maxed settings are:-

 

Global texture resolution.

Level of detail radius.

Special effects detail.

Cloud coverage density with detailed clouds.

 

I have AI traffic at 85% (I fly PMDG 737NGX and like busy airports) with other traffic at low to medium. If you think any of these are pushing things let me know please.

 

I have my doubts that it is a hardware issue. I can run other games and video editing software without any problems. This only happens in FSX.

 

I'd be grateful for any help you can give.

 

Regards

 

Iain

Memory timing in the BIOS is set to auto

 

You have the Ivy Bridge chipset but back when I had the Sandy Bridge setup I read somewhere on a tech site that ASUS boards had problems figuring out the installed RAM.  With memory frequency/timings/and voltages set at Auto, your system may run well for a period of time (like mine had) and it will pass all kinds of stress tests (like mine had) but suddenly I saw CTD's when running FSX (and only FSX).  I decided to manually change my frequency/timings/and DRAM voltages in line with the Timing Tables shown under the SPD tab in the utility CPU-Z.  Your SPD timing tables are also shown in the BIOS under the Tools Tab (believe it is still there.  I do not have your MB).  The best memory timings you can select for your system are under the X.M.P. column.  That will use your memory to the best available for your system.  You should also have your overclock using the X.M.P. profile which optimizes your memory.  You may already have this since you have an IT professional helping you out (my son is an IT professional too).  So that would be my first recommendation, to manually set your memory settings (it really is not difficult especially with the ASUS UEFI BIOS). 

 

Next, you have only 4GB RAM.  Not very much.  The max Virtual Address Space (VAS) limit in FSX (a 32-bit program) is 4GB IF you are running a 64 bit OS (and you are).  Any memory above that will be used by installed hardware and your operating system.  Since you only have 4GB's, FSX will only use about 3-3.5 GB's leaving the left for your system and hardware.  If you have more than 4GB's you could get most if not all of the 4GB's out of FSX.  You might think about getting more RAM.

 

Here's a link to a fix by Microsoft to increase the default heap limitations and give you system a little bit more room to breathe - http://support.microsoft.com/kb/947246.  Even though you are not currently experiencing out-of-memory (OOM) crashes, this fix should still be applied if you are an FSX user as FSX loves to eat memory!

 

I see no issues with your fsx.cfg settings other than I think your AI is set way too high.  Even the developers of AI software do not recommend a setting above 40%.  You'll still have plenty of AI around you to give you some immersion into the surrounding environment.  I have mine set at 30% and have more than enough AI around me.

 

 

 

Autogen is a known FPS killer.  You indicate it is not at max and that's good.  I would keep it around normal settings. If you use Autogen, make sure the Autogen "tweak" is in the Terrain section (http://support.microsoft.com/kb/555739):

　

 

Terrain_Max_Autogen_Trees=1000

Terrain_Max_Autogen_Buildings=800

 

They say with those settings you can push the Autogen slider all the way up to max (never tried it though).

 

If you have tweaks in your Fsx.cfg, you should consider getting rid of them.  Some can be more harmful to your systems performance.  Bufferpools is the main culprit.  It does not work on every system.  I personally think it was made for older systems to get the most performance out of the systems as possible.  But you have a fairly modern system.  You can easily test whether tweaks work or do not work by simply commenting out the tweak and it will not load when you start FSX.  To comment out a tweak, just place two slashes // in front of the item in your fsx.cfg (i.e., //[bufferpools]). 

 

Hope this helps.

 

Best regards,

Jim

 

Jim, thank you so much for your detailed reply. I've installed CPU-Z and I must admit, the results don't mean much to me and are puzzling in one or two respects.

 

The memory is Corsair Vengeance CML4GX3M2A 1600 C9 and looking at some reviews this memory will run at 1600MHz. However I cannot see that in the CPU-Z results. Under the Memory tab it says:

 

D RAM frequency = 666.7MHz

FSB DRAM = 1.5

CAS# latency(CL) = 9 clocks

RAS# to CAS# delay = 9 clocks

RAS# pre-charge (tRP) = 9 clocks

Cycle time tRAS = 24 clocks

 

Under the SPD tab it says:

 

Modules = 2048MB each

Max bandwidth = 667MHz

Memory = Corsair as above

SPD ext = 1.2

 

Below in the timing tables:

                                                    JEDEC#1       JEDEC#2      JEDEC#3        XMP1600

 

Frequency                                   444MHz           592MHz          666MHz         800MHz

CAS latency                                     6.0                  8.0                 9.0                9.0

RAS to CAS                                      6.0                 8.0                  9.0               9.0

RAS precharge                                 6                      8                    9                   9

tRAS                                                 16                   22                  24                 24

tRC                                                   23                   30                  34                 41

Command rate                                                                                                    2T

Voltage                                            1.5V                1.5V                1.5V             1.5V

 

Does anything strike you as being incorrect here?

 

Regards

 

Iain