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64 Meg ram chip detects as 16 Meg? 2

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AndyHo

Technical User
Aug 1, 2000
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We have 6 Pentium 120's that are getting a bit light on resources. While they are not vital to our overall system it would be nice if some improvements could be made. The Users manual for the Motherboard (AI5TY) says that it supports SDRAM to 64 meg and it has a slot that currently contains a 16 meg chip. If we swap it for a 64 the chip is still detected as 16 meg. I have searched the BIOS for an obvious solution without success. Any ideas???

Andy Holden
 
Hmm...does the board contain two different types of RAM slot? If so, the slots currently being used (as you know, you should NEVER mix RAM) may be being determined by a jumper setting - the motherboard manual MAY be more helpful there, especially since I can't find out anything about the AI5TY on the net (what make is it?)

Other than that, check the blindingly obvious - is the RAM inserted properly, put it into a different slot (some boards prefer RAM to be placed in slot 0, which is going to be ONE of the end ones :> )

Short of that, I can't suggest anything further without having some idea of what make the board is (then I can hunt down an online version of the manual if possible)
 
Check the speed of the chip your putting in.
You should find that its to fast for your MB (66MHz, 100 or 120 ). I think u might have the slowest.
Hope that will help.
 
Thanks for the ideas. The motherboard manual does not give a makers name. (Which is a concern). The ram speed is the likely problem I suspect. This is not an area that I am familiar with. The manual lists 1Mx64, 2Mx64, 3Mx64, 4Mx64 - what does this mean? The type listed is SDRAM 3.3V - what does this mean? (is this a silly question?)

If it helps. There is only one ram slot for DIMMs and four SIMM slots that have never been used.

Andy Holden
 
I had the same problem. A Pentium 200MMX CPU with 2 DIMM slots. I tried to use PC-100 RAM and got the same result you did. Turns out the front side bus is only 66 MHz. I think that may be the problem you are having.
 
You multipy the number before the "M" by 8 and that is the memory module's size in MB. The 64 tells you that that the module is non parity or no ECC (Error Code Correction). If that number was 72 it would represent a parity module that supports ECC.

Good Luck
 
just so you know ECC = Error Checking & Correcting, not "code" Karl Blessing aka kb244{fastHACK}
kblogo.jpg
 
Well I'm now convinced u have a 66MHz bus MB and the chip you've put in is either a 100MHz or a 133MHz.
The only way to sort your problem is to get hold of an older RAM chip (66MHz).

Have fun.
 
The 66 MHz bus speed seems to be it. I got around it by doing a 2 way shift. I put the 64 meg cips in some 233MMx machines and stole their 32MHz chips for the old pentium 120's. This had an obvious benefit for both sets of machines. It just means that I need to do a big upgrade on the pentium 120's sooner than the original budget intended,

OK now who plans upgrades with AMD chips in mind?

Andy Holden
 
if the AMD chips are socket7 and lower, keep the same idea in mind, because Socket7 is also used by intel, both chips have the same bus limits if they are using the same board.

in otherwords, if you have an AMD 233 or lower, chances are the board is a 66Mhtz Bus, and you'll need PC66 rams. Karl Blessing aka kb244{fastHACK}
kblogo.jpg
 
Memory modules on a Pentium system must be replaced in pairs. Later systems, Pentium II, etc allow memory add-ons or replacement singly.
 
thats ONLY if they are simms (72pin), but given the age of his chips, yea I would assume he's using simms. Karl Blessing aka kb244{fastHACK}
kblogo.jpg
 
These are Dimms - the speed is almost certainly the problem. I did notice that there are a fair number of settings in the bios that can be changed but it is now in the too hard basket and as I said before the 2 way shift has proved effective.

Andy Holden
 
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