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General discussion

mixing RAM

Aug 7, 2004 12:55PM PDT

RAM in old spare computer (Pentium II, 266MHz) is marked SDRAM. I have a strip of PC100 128 MB left over from an upgrade of another box. Can I put it in the empty slot on the old Pent II?

Discussion is locked

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Re: mixing RAM
Aug 7, 2004 1:00PM PDT

Sometimes. You can research it or just put it in and test it with http://www.memtest86.com

Be sure to look into what OS you use. Windows 95/98/ME have issues past 512M

Bob

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Re: mixing RAM
Aug 7, 2004 1:13PM PDT

If I go to control panel->system->general tab and see the new amount of RAM shown can I conclude the system will use it?

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Re: I think he means if its more than 512 in 98...
Aug 7, 2004 3:39PM PDT

If you are asking if that means that the ram is operating, yes it does and it should show when the computer is booted and counts up the ram in the memory test.

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No. Here's why.
Aug 7, 2004 10:20PM PDT

You didn't mention the OS. For instance, in Windows 98, ME, 98, 3.x and others, the areas called RESOURCES are fixed spaces of 64 thousand bytes. Adding RAM does not expand these spaces and if this is why you are adding RAM, then that won't help.

More about Memory at the same title article at http://www.aumha.org/articles.htm

The forum tip does ask you tell about your machine and the OS, so please take time to follow the instruction.

Bob

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DO NOT MIX RAM
Aug 10, 2004 2:15AM PDT

HEY, LISTEN. RAM CAN ONLY BE MIXED IF THEY HAVE THE SAME SPEED. EX. PC100, PC1500, ETC. ALSO IF YOU ARE PUTTING 128MB OF RAM IT MUST BE TWO SLOTS CONTAINING 64 AND 64 EACH ONE. GIVING YOU 128MB OF RAM. REMEMBER THAT RAM IS INSTALLED JUMPING NUMBERS. FOR EXAMPLE, IF YOU HAVE FOUR SLOTS. YOU WILL PUT THE FIST SDRAM IN SLOT 1 AND THE 2nd ONE ON SLOT 3. O.K. DO NOT BELIEVE WHAT EVERY BODY SAID IN THE DISCUSSION THEY DO NOT KNOW NOTHING ABOUT HARDWARE. I'M A SECOND YEAR COLLEGE STUDENT.

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I DO MIX RAM
Aug 10, 2004 3:09AM PDT

But I'm just an old grizzled electronics designer. It's perfectly acceptable to put a PC133 stick into a system that has PC100. The faster parts are not a problem. Slower parts would be. There is that old BX chipset issue with today's modern 256M PC133 sticks, but they don't teach you that in school.

Bob

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Re: I DO MIX RAM
Aug 13, 2004 4:16AM PDT

Man are you crazy going against Ernesto? He's a second year college student.

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Re: DO NOT MIX RAM
Aug 12, 2004 11:06PM PDT

As Robert says, no problem mixing speeds, and this old system only requires 66Mhz, so 100Mhz will work fine.

A system that old does not use memory in matched pairs, you can put any size in any slots and it will work fine.

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Re: mixing RAM
Aug 10, 2004 4:23AM PDT

Install it, PC66, pc100 and pc133 can be used together. HOWEVER, that's not always a guarntee it will/may work at least it won't blow-up the system. This is a timing issue as well as some vendor incompatibilites(generic ram) so it doesn't hurt to try. Put the fastest ram in 1st slot, but you may have to play with it, slot to slot as mentioned above. A good rule of thumb is to put the largest mb ram stick as first use. You should look at your mtrbd. specs sheet usually found at the mtrbd. makers support website, for an absolute answer if found.

good luck -----Willy Happy

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Re: mixing RAM
Aug 12, 2004 12:06PM PDT

I went ahead and mixed my RAM. That old box never ran so fast. Shows up on system properties box too. Thanks for a lively discussion.

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Re: mixing RAM
Aug 17, 2004 12:17AM PDT

To add to this discussion a little... Would the same hold true for RDRAM??? I know that you have to install this type of RAM in pairs (or with a dummy board), but do the various type/speeds/etc... of RDRAM play a major role on the operability of the memory??? I know that if you stick a ECC stick in with a Non-ECC stick, that the memory will function but only in Non-ECC mode, but will PC800 conflict with other PCxxxx sticks? Thanks!

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Mixed RDRAM = You first Mikey.
Aug 17, 2004 10:08AM PDT

As far as I know, you want the slower speed in the first pair and the faster/nonECC in the second set. No firm guidelines here.

Bob

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Re: mixing RAM
Aug 17, 2004 1:00PM PDT

When it comes to RDRAM install exactly what's already there. It lessens any problems and for all practical reasons, just is the best way to go. For the cost involved, why deal with anything else, its money well spend. Sad expensive grrr...

good luck -----Willy Happy

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Re: mixing RAM
Aug 17, 2004 12:20AM PDT

To add to this discussion a little... Would the same hold true for RDRAM??? I know that you have to install this type of RAM in pairs (or with a dummy board), but do the various type/speeds/etc... of RDRAM play a major role on the operability of the memory??? I know that if you stick a ECC stick in with a Non-ECC stick, that the memory will function but only in Non-ECC mode, but will PC800 conflict with other PCxxxx sticks? What about the FSB speed??? Thanks!