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patchar

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memory upgrade not recognized

I have a P5F85 motherboard designed around the 82430TX chipset. It has (2) 168 pin DIMM slots and (2) 72 pin SIMM slots for memory.  I have 32MB SDRAM installed in each DIMM
slot (64MB total). They are 16M-bit based with the following number written on each of the 16 chips per module: 81116822C-100LLFN  9746 M17. I wanted to upgrade my memory by adding (2) 32MB simms into the simm slots.  I needed to know if this motherboard could handle this and if any settings in the bios or jumpers needed to be changed, so I emailed the motherboard maker (to make sure) and they assured me that this could be done, as long as the
dimms were not 64M-bit and that both simm slots were filled with 32MB or less simms (same type, speed, size). The bios would recognize the upgrade automatically. The manual said it could take FP/EDO type, so I went and bought (2) simms to fill the slots. They are 72 pin, EDO, 8x32, 60ns,32MB. When I installed them, the computer only recognizes 64 MB.
Installation and memory modules are OK. Any suggestions?
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rmarotta

My suggestion:
  Never mix SIMMs & DIMMs.
(It almost always causes problems.)

Other suggestions:

Try the SIMMs alone, to be sure they're okay, and then with one DIMM installed at a time.

Try the SIMMs in a different socket bank.  Try all combinations of re-locating the modules.

Check possible jumper settings to be sure the correct DIMM voltage is applied.  SDRAM needs 3v, EDO 5v.

Return the SIMMs, buy a PC-100 64MB DIMM (to be used in future upgrades), and sell the 32MB DIMM.

Regards,
Ralph
Even if you can mix SIMMS and DIMMS (some motherboards allow it, but it is not recommended) you can only use two banks or memory on some boards (2 DIMMS, 2 pairs of simms, or a pair of simms and a dimm).  If so, then your only options are:

-Sell some memory so that you have only two banks (I would recommend you keep the DIMMS)
-I think your board will be maxed out at 64 MB, if the largest memory sticks you can use are 32 Mb.

But then again, I might be wrong.  Play around with the memory setup, and see what you can do.

Good Luck,
Jeremy
Make sure your new memory chips are seated correctly.  I'm not familiar with this board, but have seen more than one person install more memory and the chips not be fully seated.  Unless they are they won't be recognized.

Piezo's comment was the first I would have made.
Do the memory sticks "look" like they're all aligned properly and are they firmly seated when you wiggle them?
Avatar of patchar

ASKER

I have taken out  the dimms and I get 64MB, so the simms are alright. I then put one dimm back in at a time. Still reads 64MB. I took out the simms and the dimms  read 64MB, so all of my memory is alright.  I have rearranged the modules, and double checked each installation. I can't find any jumpers for voltage settings though and I still  get 64MB no matter what. I have emailed the motherboard company and I'm waiting for their answer, but then again, it's their answers that have gotten me where I'm at. :-)  I guess you guys are right. My only problem is what kind of memory do I get?  The manual says to use 3.3V, unbuffered, 66.7 MHZ, CL3, 8Mx64, 168 pin sdram. I have seen all of these specifications when looking for memory, except for the 66.7 MHZ. Would one that said 10ns work?  And if I got (1) 64MB module, would it work with my other 32MB sdram for the time being?
patchar,
The 64MB DIMM should work fine if the motherboard supports it.  It doesn't have to match the capacity of the other one(s).
As I said in my prior comment, I suggest you go for the PC-100 spec. SDRAM because you will then be able to use it again when you upgrade.  It's not much more expensive than a 66Mhz module, and newer Pentiums running about 350MHz or more require it.

Regards,
Ralph
patchar,

I thought that the tech told you that 64M dimms would not work.  Anyway, then you should stick with the 64 M of dimms you have now, and try to sell the simms as soon as you can if you can't return them (I VERY seriously doubt you can since these are preexisting modules), while they are still in demand!  If your board does support 64 Mb modules, them you could always throw in a 64 Mb dimm and use it with one of oyur 32 Mb chips, although I don't think it would be worth the extra cost.  If you can return the new modules, you could go for a 64 Mb, like ralph suggested, since it will be more easily used if you buy a new system eventually.  But it looks like your board maxes out at 2 memory banks, so you can't go with the 128 you were trying for.

Regards,
Jeremy
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ASKER

The manual said the motherboard can handle up to 32MB for each simm socket (64MB) and 32MB for each dimm socket (64MB), only when simms and dimms are mixed, . It can take up to 128MB modules if only simms or dimms are used (256MB). So you're sure the PC100 modules will work, even though the manual doesn't mention them?  This may sound like a stupid question but does the speed referring to memory, relate to what the module can take, or runs at? In other words, does the 66Mhz mean the module can handle up to that speed, or it takes 66 MHZ to work? And just for my information, is 10ns the same as 66MHZ or are they 2 different things?
Avatar of patchar

ASKER

The manual said the motherboard can handle up to 32MB for each simm socket (64MB) and 32MB for each dimm socket (64MB), only when simms and dimms are mixed, . It can take up to 128MB modules if only simms or dimms are used (256MB). So you're sure the PC100 modules will work, even though the manual doesn't mention them?  This may sound like a stupid question but does the speed referring to memory, relate to what the module can take, or runs at? In other words, does the 66Mhz mean the module can handle up to that speed, or it takes 66 MHZ to work? And just for my information, is 10ns the same as 66MHZ or are they 2 different things?
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rmarotta

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Thank all of you for your help!