747-400 FSX Technical Specs & Performance
From PMDG Ops
Contents |
Introduction
FSX brings many new benefits and vastly superior visual capabilities to Microsoft Flight Simulator. FSX represents the beginning of a shift in design philosophy in the Flight Simulator franchise as Microsoft attempts to bring the simulation up to modern gaming standards, including enhanced graphics, powerful mission based gaming options, and infrastructure designed specifically to support the development of scenery and aircraft ad-ons. This unprecedented and documented interoperability is designed to reduce the amount of bit-twiddling required of add-on manufacturers and increases the robustness of add-ons produced for the community.
While improving the base platform to include these new features, the Microsoft development team also attempted to maintain compatibility with many legacy development techniques. Doing so has been achieved with some costs. These costs come primarily in the area of program overhead, lower frame rates than FS2004, and a decreasing benefit from high end hardware.
As many in the flight simulation community have been exposed to extraordinary visual and world modeling in other gaming genres, there has been increased desire in the community to see the Microsoft development team “clean sheet” the Flight Simulator franchise in order to bring all of the newest and best technology to the forefront. Building a new version of Flight Simulator from the ground up would have the side effect of eliminating all existing add-ons from use, as the structure upon which most existing scenery and aircraft add-ons work is legacy structure that is inefficient, ineffective and would be replaced in a new sim.
Fortunately, FSX is a half step in the direction of rebuilding our favorite simulation platform. Unfortunately, FSX is a half step in the direction of rebuilding our favorite simulation platform. In other words, the user community and the development community is working with an FSX platform that offers much greater capabilities in some areas, but isn’t by any means a perfect solution for developers OR users. In the end, it is a significantly better platform from the viewpoint of a developer, and to this end PMDG has worked very hard to ensure we take full advantage of everything FSX has to offer.
The PMDG 747-400X is not a “port” of our existing product to FSX. Instead, the PMDG 747-400X is an entirely new product designed and built to take advantage of the new FSX platform.
The development and testing process for the PMDG 747-400X has been a difficult one, as we have blazed new trails and learned new techniques in working with FSX. Through this process we have developed a significant base of knowledge regarding what “works” and what “doesn’t work” with respect to FSX. This document is designed to help you gain from our knowledge.
Hardware and Operating System
First, let’s address the issue of Operating Systems. At PMDG we have tested FSX on a broad range of machines, and we have some strong, clear recommendations to make regarding your selection of operating system when using FSX.
PMDG strongly discourages using FSX in the Windows Vista operating system, regardless of how much processor speed, video capability or memory you may have.
If you intend to use FSX and stick with only the default aircraft, and do not intend to add high density scenery or weather programs, then FSX should operate effectively on any machine that uses Windows Vista and has at least 2GB of memory.
Vista and OOM Problems
If you intend to use complex add-ons such as the PMDG 747-400X, and/or add complex scenery and/or weather packages, Windows Vista in it’s current form will cause you nothing but frustration and heartache through unreliable performance, Out of Memory Errors (Operating System Generated) and random unexplained CTDs (that are almost certainly uncaptured OOM errors.)
Why does this happen? Windows Vista has drastically changed the way the operating system handles hardware memory management. The full explanation is very technical and involves an aspect of the OS called “user address space,” but the end result is that the combination of the 747, FSX and Windows Vista appears to be highly susceptible to OOM and CTD errors triggered when the operating system fails to manage memory correctly.
This type of error is not unique to FSX as they occur in many other games with high memory usage. This has been documented by several websites like AnandTech and HardOCP. The combination of the way Vista manages memory, FSX’s already high RAM overhead, and our intensive cockpit systems simulation simply overload the amount of user address space available and the sim crashes.
There is some thought that the 64bit edition of Vista might be a potential solution to the issue due to its increased memory handling abilities versus the 32bit edition. We have not been able to test this however, but you are welcome to do so. If you are successful in using either edition of Vista without these errors, we would like to hear from you in regard to your system configuration and anything you may have done to make that possible.
We have been hoping that this problem would be resolved in Windows Vista SP1, but based on currently available information, it does not appear that this problem will be fixed.
You can read more about the Windows Vista memory handling problems here:
AnandTech - Windows XP, Vista and the 2G Barrier
For best performance, PMDG recommends installing FSX under the WinXP Operating system.
Processor
FSX, because it has retained a significant amount of legacy compatibility, is a very processor and memory intensive simulation. We have found that the biggest limiting factor when running FSX is the processor.
Single core processors have a hard time running FSX in conjunction with complex add-ons and scenery. This becomes especially true if your machine has 2GB or less of memory.
Multi-core machines do a significantly better job of running FSX and the PMDG 747-400X. As always, the faster the processor and the more memory available, the better the performance. Memory: When running FSX and the PMDG 747-400X on a WinXP machine, optimal performance is found on machines that have 2GB or greater of memory installed. (note: if you opt for more than 2GB, be sure you install dual channel. If you install 3 DIMMs you may suffer a performance hit!) WinXP is capable of using only up to 3GB of memory (most of our machines have 4GB installed in order to maintain dual channel), but does so very effectively, and operates without any of the instability experienced on Vista based systems.
When running FSX and the PMDG 747-400X on machines with 2GB or less, performance begins to suffer.
Video Card
Since FSX is a processor and memory intensive product, the vast majority of high end display cards currently being used by simmers will be effectively under-utilized. In short, this means that the more powerful your card, the more hardware processing you can use to improve the visuals of FSX because the simulation isn’t using your card to the extent of its capabilities.
We have found during testing that setting the “visual detail” sliders full left or full right doesn’t have as dramatic an impact on in-sim FPS as in previous versions of FSX. This is indicative of the CPU/Memory carrying the load within FSX.
Predicting Your Performance
In order to help you predict the performance you will see when using the PMDG 747-400X on your machine, we asked a number of our Technical Advisors and Developers to conduct a series of tests, reporting the resulting frame rates in a chart.
This performance testing shows a strong bias toward multi-core machines running WinXP with 3GB of memory. Two of the machines tested were dual-boot capable between Vista and WinXP, and they provided an interesting view of the performance difference between those two operating systems. (It should be noted that the Vista machines showed significant instability running FSX, and this instability was related to the Operating System producing OOMs as documented above.)
The performance matrix used three scenarios, and asked the user to report FPS in both the PMDG 747-400X and the default FSX 737-800.
The three different scenarios are described as follows:
All three tested at CYVR (Vancouver BC, Canada) with the "Fair Weather" and "Day" presets selected.
- Scenario A
GRAPHICS: Lens Flare - On Light Bloom - Off Advanced Animation - On Global Texture Resolution - High AIRCRAFT: Shadows on Ground - On Self Shadows - Off Landing Lights Illuminate - On SCENERY: Detail Radius - Medium Mesh - 100% Mesh Resolution - 19m Texture Resolution - 1m Water Effects - High 1.x Scenery Complexity - Normal Autogen Density - Normal
- Scenario B
Same as Scenario A, except: SCENERY: Mesh - 88% Mesh Resolution - 38m Water Effects - Medium 1.x
- Scenario C
Same as Scenario B, except: SCENERY: Autogen Density - None
The performance matrix is linked below in PDF format:
747-400 FSX Performance Matrix
