After reading advice from many people I consider much smarter than me concerning computers, I switched my FSX rig from Vista Ultimate 64 to XP x64.I have to say, I dont get problems with black screens, missing textures, and disappearing VCs anymore, I can switch in and out of the full screen with no worries of freezing, and I get very good frame rates with settings on quite high.However, I have for the past few days now been trying to fly a long haul flight with the PMDG 747 and the machine freezes up on me usually around three hours into the flight. Total freeze, unresponsive, the only thing I can do is shut the machine down.Now I removed most of the overclocking I had on the machine, focusing more on just having the machine run at lower temps, set my memory to the XMP profile. I then was able to make a 5:30 hour flight. But today I tried another 5:00 plus flight and again around three hours, the whole machine just locked up. I am hear asking for advice, possible cause for the problem, possible solutions. I really just have no idea. I had FSX running quite fine on Vista Ultimate after turning down the sound quality to curb the black screen and texture issues, but that only did so much. I saw NickN, a man's opinion I have come to greatly respect, as he certainly knows what he is talking about, made a very good point that FSX was designed and tested on XP, so it should run with far less problems on XP 64. And aside of the feezing, FSX does run great, which just makes it all the more puzzling to me. I dont seen any texture degredation, sound problems, or frame rate, or any other types of performance issues prior to the total freeze.My theory was, and still is, that it is a memory issue. That after about three hours some sort of critical mass is hit and the computer just stops working. However, the memory at the current XMP timings of 1600 and 8-8-8-24 has passed linx, prime95, and memtest, so I do not think that is the problem.XP x64 does seem to run fine, aside from a plethora of disk.sys stop errors after I installed it, which were subsequently fixed after changing the order in which all the SATA Hard Drives and Optical Drives were plugged in.If anyone has an idea what is wrong with my system, please lend a fellow flight simmer a hand. Thanks, Scott

After reading advice from many people I consider much smarter than me concerning computers, I switched my FSX rig from Vista Ultimate 64 to XP x64.I have to say, I dont get problems with black screens, missing textures, and disappearing VCs anymore, I can switch in and out of the full screen with no worries of freezing, and I get very good frame rates with settings on quite high.However, I have for the past few days now been trying to fly a long haul flight with the PMDG 747 and the machine freezes up on me usually around three hours into the flight. Total freeze, unresponsive, the only thing I can do is shut the machine down.Now I removed most of the overclocking I had on the machine, focusing more on just having the machine run at lower temps, set my memory to the XMP profile. I then was able to make a 5:30 hour flight. But today I tried another 5:00 plus flight and again around three hours, the whole machine just locked up. I am hear asking for advice, possible cause for the problem, possible solutions. I really just have no idea. I had FSX running quite fine on Vista Ultimate after turning down the sound quality to curb the black screen and texture issues, but that only did so much. I saw NickN, a man's opinion I have come to greatly respect, as he certainly knows what he is talking about, made a very good point that FSX was designed and tested on XP, so it should run with far less problems on XP 64. And aside of the feezing, FSX does run great, which just makes it all the more puzzling to me. I dont seen any texture degredation, sound problems, or frame rate, or any other types of performance issues prior to the total freeze.My theory was, and still is, that it is a memory issue. That after about three hours some sort of critical mass is hit and the computer just stops working. However, the memory at the current XMP timings of 1600 and 8-8-8-24 has passed linx, prime95, and memtest, so I do not think that is the problem.XP x64 does seem to run fine, aside from a plethora of disk.sys stop errors after I installed it, which were subsequently fixed after changing the order in which all the SATA Hard Drives and Optical Drives were plugged in.If anyone has an idea what is wrong with my system, please lend a fellow flight simmer a hand. Thanks, Scott

Hi Scott,I had similar issues with the PMDG MD11 on XP64pro. What ultimately saved the day for me was to completely remove my Soundblaster X/Fi card & associated drivers from the system and use onboard sound from my motherboard. As a result, I have been operating without any freezes.

Scott,I am confused. Your signature says you are running 6GB of Corsair 1200 MHz DDR3 memory and in your post you say you are running at XMP profile settings of 1600 Mhz at 8-8-8-24 timings. If this indeed is the case relax the memory timing to the stock 1200 MHz. Prime95 and Linx cannot stress your computer as heavily as FSX will. I had the same issue on one of my other rigs and backing down the memory timings cleared the issue.Are you attempting to do anything when the system freezes? and when the sytem does freeze what happens to your sound?

Hi Scott,I had similar issues with the PMDG MD11 on XP64pro. What ultimately saved the day for me was to completely remove my Soundblaster X/Fi card & associated drivers from the system and use onboard sound from my motherboard. As a result, I have been operating without any freezes.

I too use on-board sound. I have no other sound cards installed.

Scott,I am confused. Your signature says you are running 6GB of Corsair 1200 MHz DDR3 memory and in your post you say you are running at XMP profile settings of 1600 Mhz at 8-8-8-24 timings. If this indeed is the case relax the memory timing to the stock 1200 MHz. Prime95 and Linx cannot stress your computer as heavily as FSX will. I had the same issue on one of my other rigs and backing down the memory timings cleared the issue.Are you attempting to do anything when the system freezes? and when the sytem does freeze what happens to your sound?

Sorry for the confusion, but my signature is a typo. They are indeed 6 GB of 1600 MHz DDR3.As far as what I am doing, I am doing nothing. It is a long haul flight, and I have been in cruise for well over an hour. I enter in the wind data into the FMC, maybe step climb, and every thirty minutes, the FS2Crew FA calls me and asks me if I need anything.Everytime I had the freeze, I was not touching the machine. I was sitting in front of it, either reading a book, or looking at weather reports on my laptop, or scanning my binder of charts for what my approach might be. The first time it froze I immediatley was aware of it because the sound started skipping like a record, repeating the same second of engine sound or so, and the machine was frozen. This last time however, the sound seemed normal, but I noticed the PFD was no longer updated the DTG milage, and FSC was showing the aircraft in the same location, so I knew it froze. After trying to ctrl-alt-del, alt-tab, alt-enter, all key combos to come back to life, I was able to then move the mouse for a litle bit, 10 seconds maybe, but FSX remained frozen,and the sound cut off. As far as the memory goes, all tests well with memtest, and corsair says that the sticks are guaranteed to work at the previously stated XMP profile.I am not thinking it is a OOM error either, since I have seen those and the computer is not getting a stop error or CTD, but rather just stopping in mid stream, and I wonder if maybe it is the display driver perhaps crashing. I am using nVidia latest what ever number that is, 196.something i think.