Win 98 memory above 512meg

By johnny5 ยท 17 replies
Mar 5, 2002
  1. How do you install more than 512meg of memory without getting an error message in Win 98 SE?
  2. svtcobra

    svtcobra TechSpot Paladin Posts: 761

    What is the error message?

    from what I have read and experienced, that much ram is useless in Win98se. You would have to upgrade to Win2k to see a difference.

    Also, your mobo bios might need to be updated to see more than 384mb. This is why you might be getting an error message. List your system specs so I can figure out what your maximum ram is . Also, one of the ram chips could be defective. There could be a number of different reasons why you are getting an error.
  3. Rick

    Rick TechSpot Staff Posts: 4,572   +65

    The answer to the majority of your Windows problems:

    Possible answer to your specific problem #1:;en-us;Q253912

    Possible answer to your specific problem #2:;en-us;Q146912

  4. Mictlantecuhtli

    Mictlantecuhtli TS Evangelist Posts: 4,345   +11

    I wonder why M$ tells users to limit their free memory below 512M. I had no problems with min- & maxfilecache being 65536 or something like that. I didn't use maxphyspage setting at all.
  5. DSMF

    DSMF TS Rookie

    Here is an explanation of Vcache and how Windows handles memory plus how to enable/disable MapCache with a link to a program that will allow you to configure Vcache in the System.ini file from one GUI....

    Windows 98 supports the mapping of cached pages to increase the amount of memory available to running applications. The Windows 98 memory manager architecture divides memory into 2 parts:

    - Protected-mode disk cache (VCACHE)

    - Memory allocated to run programs and hold data (VMM)

    Reading from memory is much faster than reading from the hard disk. VCACHE improves performance by reducing the number of times the hard disk is accessed. A process in memory will demand a particular section of code; if that section of code is in VCACHE, it can be accessed and used much more quickly than if that section of code needs to be read from a file on disk. For example, if you were to launch an application, close it, and then shortly thereafter launch it a second time, the application's launch time would now be noticeably reduced. This is a result of copying much of the application from VCACHE instead of the hard disk.

    Memory allocated to the disk cache is not available to executing
    processes. Reducing the amount of memory available to running
    applications negatively impacts performance by increasing the amount of data swapped from memory to the hard disk. Once again, reading from memory is much faster than reading from the swap file on the hard disk.

    In Windows 95, there are two instances of some code in physical
    memory; one instance stored in the disk cache to reduce the time
    required to load the application should it be invoked again, and
    another instance in VMM for the running application. Eliminating the instance of the data in the cache would increase the amount of memory available to VMM, but would negatively impact application reload times.

    Windows 98 supports the mapping of cached pages to increase the amount of memory available to running applications. Memory mapped I/O from the cache eliminates needless duplication of data while the application is running. Application code is loaded into VCACHE, and then executes out of the cache rather than having to be copied to another part of memory before it executes. When the application is closed, the memory manager labels the space that application was using as not currently being used to maintain the benefits of caching--if the application is not restarted, that space is given to other tasks. If the application is restarted, the application still exists in the cache, maintaining improved application reload times.

    Windows 98 maps cached pages by default. This performance enhancement can be disable by creating a MapCache entry in the registry key


    If the MapCache entry does not exist, Windows 98 will map cached pages. Creating the MapCache entry will disable the mapping of cached pages.

    To create the registry entry for MapCache:

    1. Select MAPC_OFF.INF found in the \Tools\MTSutil folder on the
    Windows 98 CD.

    2. Right-Click MAPC_OFF.INF.
    Hold down the SHIFT key and press the function key, F10.

    3. Choose INSTALL to create the entry for MapCache.


    Refer to the previous section for information concerning the mapping
    of cached pages.

    Windows 98 will map cached pages if the entry for MapCache is

    To remove the registry entry for MapCache:

    1. Select MAPC_ON.INF found in the \Tools\MTSutil folder on the
    Windows 98 CD.

    2. Right-Click MAPC_ON.INF.
    Hold down the SHIFT key and press the function key, F10.

    3. Choose INSTALL to remove the entry for MapCache.

  6. ldogg

    ldogg TS Rookie Posts: 33

    Yeah I don't think windows 98 supports more than 512 megs I think that's why my 524 megs of ram produces a memory address error or something on some memory test I ran.
  7. boeingfixer

    boeingfixer TS Rookie Posts: 1,006

    Maximum PC did an article on this awhile ago with 98. ME and 2000. Only 2000 was able to efficiently use RAM above 256. In their test, the ME and 98 machines actually slowed down after more than 256 was installed. 98 and Me cant use like over 196 of ram. It doesn't know how to use the extra.
  8. Th3M1ghtyD8

    Th3M1ghtyD8 TechSpot Paladin Posts: 664

    You have to change the VCache settings in order to use more than 512Mb. I am currently working on a Tweaking program for all OSes and I am in the process of including this fix.

    As soon as the beta is ready I will post the link in the forums, so that you lot can test it.

    Beta will probably be out sometime next week.
  9. TS | Thomas

    TS | Thomas TS Rookie Posts: 1,319

    I think the problem was something along the lines of Vcache wasn't releasing the used RAM. So you had to limit it & you'd be fine.
    So it can work finre with it other than wanting to limit the maximum size for vcache
  10. kapeed1986

    kapeed1986 TS Rookie Posts: 19

    RAM Blues?

    Now that MS has officially announced no more support for Win9x users, it'd be better u switched on to WinXP .. It is 1000 times better than 98 ... I've been using XP for over 2 years and it has crashed only ONCE !
    even serious errors are done with by XP reboot and voila ..u're up and running .. unlike a reinstallation of OS in the case of 98 !
  11. Tokyopete

    Tokyopete TS Rookie

    limited to 512?

    Certain Intel CPUs will only accept up to 512 with Win98SE installed. These are in the 715/745 series cpus. Asus mboards are also subject to this limitation with Win98SE.
    There is nothing that can be done to change or increase about 512!!!!! I have an old board still running which has the limitation. The computer runs perfectly as long as it is regularly defragged.
  12. It has nothing to do with the motherboard or CPU. Win9x is the problem. The OS cannot address any memory above 512MB. The fix is to simply restrict the vcache and that will prevent any further crashes.

    In all honesty there isn't much point in running this OS any more unless you want to get certain old programs/games working that won't run on 2k/XP/Vista.
  13. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,742   +421

    Maybe not anymore, but in 2002 when this thread was created it was :)
  14. Too true... I used to run Win98 as late as 2003 and I remember having to add those lines to the vcache section.
  15. Tokyopete

    Tokyopete TS Rookie

    512 limitations

    Asus TUSL2-C, CUSL2 motherboards with Intel 715 cpu are limited to 512 with Win98SE only BUT other motherboards such as Abit can use up to 768 so it can depend on the motherboard and cup whether or not there is a limit at 512. I know because I have the above mentioned motherboards in use today.
    Vcache settings can be changed quite extensively but it recommended to find a site on the internet that will explain what to do in detail. Seek and thou shall find.
  16. Tokyopete

    Tokyopete TS Rookie for full information on the v-cache and what to do with various os such as Win98Se etc. As I mentioned in another post, I have reset the v cache settings and other settings to deal with the 512 limitation.
    I am absolutely sure that Asus TUSL2-C and CUSL2-C motherboards with Intel 715 cpus when Win98SE is used are restricted to 512 so your assumption that 524 is too much is correct. celeron 1400cpus also suffer the same limitation.
  17. DataCom

    DataCom TS Rookie

    I have an Asus P5P800 SE and it is a dual boot system. It's running millenium & winxp pro. Millenium for older programming programs not xp compatable. There is 1 gb of memory installed and currently millenium is limited to 512mb. Last year I tried a new install of millenium for test purposes and noticed it didn't need the 512 limitation. The millenium install that does require the 512 limitation does a blue screen saying system halted on boot if the 512 limitation is removed. I considered re doing the windows install with the 512 limitation but there is would be a ton of work involved and some of the stuff installed I don't have the install's for anymore.
    So some apps might be lost which is not a good choice. I read once that the VMM dir created during install is based on the amount of ram installed during windows install. I have tried an overlay but it had no effect. The other choice is exporting the software keys of the registry and importing them in to a fresh install. I'm not sure which keys I need but I have seen it done before.

    any ideas?

  18. Starcruiser322

    Starcruiser322 TS Rookie


    I can't even get over 128 MB on my 98SE!
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