How to make use of 4GB RAM in XP SP3?

[Wozza]

So, I have increased RAM to 4 GB, and no more CTD over Manhattan X.

BUT...

I still get the "Black Forest" or "Pincushion" effect of vertical black spikes that seem to rise from the terrain when flying over dense scenery like Manhattan X. I was hoping the increased RAM would alleviate this annoyance.

Can anyone please explain what is causing this "Pincushion" effect?

- Jeff

Hi
Try playing with the
[BufferPools]
PoolSize=
in the fsx.cfg.if the entry's there try removing it
if not add it and play with the size.The default is 1000000. Increasing it to 5000000 or 10000000.Some systems work better without it some sytems work better if it there.
Wozza

 

[harleyman]

So, I have increased RAM to 4 GB, and no more CTD over Manhattan X.

BUT...

I still get the "Black Forest" or "Pincushion" effect of vertical black spikes that seem to rise from the terrain when flying over dense scenery like Manhattan X. I was hoping the increased RAM would alleviate this annoyance.

Can anyone please explain what is causing this "Pincushion" effect?

- Jeff

YUP Like VORA said your sliders are to far right..you are pushing your vid card mem to far..back off and see how it does...

 

[cvearl]

Caveat - If I misunderstand this issue, sorry. My understanding is that installing XP32bit SP3 with 4GB RAM is the best you can do with 4GB physical RAM. There are no other hacks other than running lean as you can with as little crap in the background as possible.

Besides the information below... Physical address extension is enabled by default since SP2 of XP if that is what we are talking about here. The article below explains the whole XP 32bit address limitation of XP 32bit but here is the long and the short of it. Let's say you have 4GB installed physically.

XP 32 can only use a memory address space of 4GB. It then "RESERVES" addresses in that table for loading every little bit and piece in your computer (Devices and so on like a SATA controller... They all need an "address RANGE" to exist in so that the Os can communicate with it) leaving 3.25GB (3402084 in task manager) of RAM free for the system. XP loads up and uses some of that. Typically after XP loads into memory you will have about 2.9GB free. If you have 4GB physically installed that is.

The more RAM on the video card, the less you have free to the OS is the concept because the OS needs to reserve the address space for the RAM on the video card. I have a 512Mb card and I have XP SP3 reporting 3.25GB free. Theory is that if it were 1GB card I would have less reported available to the Os because the addresses for that 1GB will need to be reserved.

If you have a 2GB PC with a 1GB Card and a 32bit XP install. You likely have very little left for the FSX app to run in.

http://www.dansdata.com/askdan00015.htm

"a note about the /3GB, /4GT and /PAE Windows boot.ini switches, too, because they often come up when people are talking about 4Gb-plus Windows PCs. They are all useless to you. You do not want them. /3GB and /4GT are config settings for different versions of Windows that tell the operating system to change the partitioning of the 4Gb 32-bit address space so that applications can use 3Gb and the OS kernel only 1Gb, as opposed to the standard 2Gb-each arrangement. They don't help at all with the 3Gb barrier, and most applications don't even notice them, so desktop users lose kernel memory space (and system performance) for no actual gain at all. The /PAE boot.ini switch, on NT-descended Windows flavours, activates the Physical Address Extension mode that's existed in every PC CPU since the Pentium Pro. PAE can also be enabled by the /NoExecute entry in boot.ini, which turns on support for the NX bit which you probably also don't actually want.

ECT...

In regards to that blogs comments on the /3GB and the USERVA setting trick, it does not make your computer recognise more RAM. I understood this wrong. The "USELESS TO YOU" meant it was useless in that context. Almost no apps are large address aware and would not see the extra VAS address space you freed up anyway (FSX SP2 is though). That and it CAN be set wrong and mess up windows and also introduce some driver issues in some applications. That said, Phil from ACES had suggested this setting as it changes the management of the memory that IS available so that you can move a little from the OS side to the APP side to give MSFS a litte more elbow room. It will not change how RAM is reported when you RIGHT click My Computer and go to properties or "break the 3.4GB Barrier" or anthing of that nature. You cannot do that regardless.

The best document I have found on the matter. Almost from the horses mouth...

http://www.fsdeveloper.com/wiki/index.php?title=OOM_Error&diff=prev&oldid=4623

"QUOTE"
Incidentally, it's also important to note that the amount of memory on a video card can actually hinder performance rather than help...
...that is because the video card's memory addresses are mapped to the operating system's slice of VAS, and therefore reduces the total number of Virtual Addresses available the operating system...
For example, a video card with 512MB of onboard RAM will consume 512MB of the available operating system's slice of VAS, so robbing too much from the OS's slice can cause a lot of problems. As always, this is a balancing act...
FINE TUNING VAS As I stated previously, since it's a case of "robbing Peter to pay Paul," it may be best to allocate LESS than a full GB of VAS to applications, which is why Phil Taylor recommends using /2560 rather than the full /3072 MB.

NOTE: The following applies only to WinXP users:
<HR>In your boot.ini file, if you have added the /3GB switch already:

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin /fastdetect /3GB
To "fine tune" the actual amount of VAS allocated, you need only add another switch to the end of the entire entry:
/Userva=2560
or whatever size you wish, keeping in mind the 1MB contiguous limit of FSX. In such a case, using any number that isn't a multiple of 512MB simply doesn't make much sense...

NOTE: The following applies only to Vista32 users:
<HR>BCDEDIT /set increaseuserva 2560 BCDEDIT /set increaseuserva 3072


WARNING!

It is possible to starve the operating system's slice of VAS to the point that your system will no longer boot!
If this happens, you must reboot the computer into "Safe Mode" (which bypasses the /3GB switch, and then edit your boot.ini (WinXP) or use bcdecit (Vista) to reduce the size of the application slice of the VAS. "

Retrieved from "http://www.fsdeveloper.com/wiki/index.php?title=OOM_Error

Anyway, this sounds strange at first but here's the math but remember, the trick is trying to reduce the instance where either the OS or FSX actually runs out of space...

Without the /3GB switch = 2GB for apps and 2GB for OS to address. This is the default. If FSX spills over 2GB it starts using the PAGE FILE. Well Windows does it for FSX as it ultimately looks after this.

With the /3GB switch = 3GB for apps and 1GB for the OS left. This is shaving it close. If the video card uses 512MB of address space because it has 512MB then the Os is left with 512MB for itself to run. If it cannot do all it's routines in that space it uses the PAGING FILE on the hard drive for Virtual RAM and when it is swapping things in and out of there, you get reduced performance system wide. If you have a 1GB card? OS slice of VAS = 0. Not sure if your system would run well or not now at all.

To tweak the VAS to protect you from overuse of PAGE FILE (drive thrashing and other related performance problems), consider how much video card RAM you have. using the /Userva=2560 switch tells windows not to use the full /3GB for the APPs slice of VAS but tweak it down to 2.5GB and leave 1.5 for the OS. It's a compromise that gives an extra 512MB address space in VAS (from 2 to 2.5GB) to give FSX SP2 512MB more RAM to play in. All the while this gives the OS 1.5GB instead of only 1 as the /3GB switch alone would have done. Now you can get a 1GB card installed and still have 512MB available to the OS. But to me that still sounds low. I am betting you would want to NOT use the /3GB /Userva=2560 in the case of a 32bit OS and a 1GB card to be on the safe side. But then you lose the 512MB boost for FSX's extra slider settings.

The OOM error is not always an error or a crash. It can manifest as spiking terrain that looks like fur growing out of the ground, blue or green squares that come and go on the ground, floating autogen objects in mid air and cracking sound from the engine. These are all signs that you are rubbing up against the computers system resource limits.

I hope anyone that had trouble with this (like I initially did) can learn from what I have tried to lay down here. I invite any corrections from anyone who knows better that I do. I enjoy being corrected because I like to know exactly what is what.

C.