Memory ID

[TomTGC]

Bought some used memory: 1 stick of 128MB Ram 66 mHz. Took EDO RAM out and installed the 128MB on 486 computer running with 233mHz. Computer boots up fine and sees 65MB Ram, not 128MB. Is there something in the BIOS that I need to change? Don’t have motherboard manual. Did I get ripped off buying a 64MB stick instead? On the memory it does say 128 on it. Any advice would be appreciated.

[ranchdog]

Hi Tom...

With the BIOS chip currently on the 'ol 486 Mboard 64MB looks to be all she can handle. So any thing above that isn't being recognized.

If you determine the Mboard Mfg and go to thier website, browse thru the archive section and try to locate your Mboard. Then check on a BIOS upgrade (flash). And this is really going to be a longshot at best.

How much RAM did you have to start with, 32MB ?

Luck.

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......Indecision may or may not be my problem......
...... Kickin' A Rock....

[mjc]

I second that motion...you most likely have hit, like ranchdog said, a BIOS wall or even some other sort of limit imposed by the design of the board, back in the days of the 486 RAM ran several $$ per MB so manufacturers and consumers alike weren't all that concerned about going much higher than 32 or 64MB, so many boards were limited to that amount...

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mjc
Links list:Computer Links (http://www.dreamwater.org/tech/mjc/index.htm)

Celts are the men that heaven made mad, For all their battles are merry and their songs are all sad.

[PostCode]

Another thing to condiser is cacheability of the chipset. Like modern chipsets, they can only address so much physical RAM. I know that older Pentium and even newer ones have limitations as to how much physical memory that can address. The 430TX chipset for example could "see" 256MB, but used only 64MB of that. The 430HX was able to see 512MB and cache all of that. So, of course the HX was a much better option than the TX when it came to memory size. It was also a lot more expensive like mjc points out about price. Newer chipsets are able to cache larger amounts of physical RAM, 1GB and up and since the price of RAM is falling and will continue to do so for at least the next year, the size of physical RAM that a given chipset is able to cache may also increase. In the end, the 486 motherboards also had limitations in them, not by design, but rather an effect of design. The people designing motherboards knew what software was out at the time and what the market was after. As for what your motherboard can actually cache, I would guess it's 64MB, but may be 32MB. And this is the same reason your motherboard cannot "see" the memory beyond the 64MB barrier. It's not designed to do so as ranchdog points out. Just wanted to let you know about another aspect in motherboards and memory. Cacheability. Hope this helps.

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[TomTGC]

To ranchdog, mjc and PostCode, thank you so much for answering my question and sorry I haven’t responded sooner. You guys are good!!