Memory upgrade

Probably, but it depends on the motherboard you have.

Inmost cases, SDRAM can be mixed with no problem.

In any case, if you physically install the RAM correctly, and it does not work, you can just remove it.
There should not be any damage done.

I hope this helps !

First, there seems to be some confusion about SDRAM and DIMMs. They are the same thing. DIMM is the card that SDRAM comes on and, for the purposes of your question, SDRAM does not come on anything else.

So you have 3 sticks (or DIMMs) of 128 MB PC 133, 64 MB PC 100 and and 16 MB of PC100 or PC 66.

You can install it all on the same motherboard. The RAM will default to the lowest speed, but PC 66 vs PC 100 vs PC 133 is irrelevant as you will see no difference in performance, so I wouldn't worry about it. Some 16 MB DIMMs were 5V, and it's probably 66 MHz, and 16 MB won't add much to performance - if it makes any difference at all! Try the 128 and 64 MBs together first. Another 16 MB is not worth the grief and I would not bother using it.

Macrobeat: I disagree strongly with your assessment that he'll see no difference in performance between 133MHz RAM and 66MHz RAM--this would only be the case if he were running an old Celeron with a 66MHz FSB. Faster RAM does make a difference, even on strictly application-based benchmarks like WinStone.

Pjknibbs, there will be a difference, but no way of a comparison, as installing the additional 64 MEG will get an extra 64 MEG, but drop the 128MEG down to PC 100. I think losing the top end of the 133 is worth-while if getting an extra 64 meg of physical memory to play with. Windows likes it's memory, and the system will probably run better with the more ram running slightly slower.

GR.

pjknibbs, faster RAM does make a difference. On Sysmark 2001, under tightly controlled conditions, between PC66 and PC 133, it's about 0.4% but, for all practical purposes that's not worth considering an increase. On other tests it's even less. PC magazines have been perpetuating this myth about PC 133 RAM and they are now slowly agreeeing that we were right all along. Even PC2700 is not as much of an increase as most people believe :-)

We do tests all day long (we ship about 200 PCs a year for review and each has at least 30 tests run on it with various tweaks/substitute parts etc, see: www.poweroid.com). Trust me on this one :-)

Macrobeat: That may be true for SysMark, but in virtually any high-end performance test faster memory shows faster performance--this is especially true in 3D games and high-end software like 3D rendering packages. Tom's Hardware runs a wide range of benchmarks on the systems they get for review, and they generally show benefits from faster RAM.

Googlyralph makes a better point in that 192Mb of RAM is probably going to be faster than 128Mb purely due to the reduction in disk access under Windows, although even then I wouldn't go any further than that--adding the extra 16Mb DIMM would be pointless, IMHO.

pjknibbs: Actually, they don't, and we do run virtually every high end performance test from MB to Quake to SiSoft to the entire Mad Onion and ZD test suites, several times on each test configuration.

While Dr Tom's is probably the best known there are a lot of tech sites that do even more detailed testing. Show me a published test that indicates clear & substantial difference in performance between PC100 and PC133 (if you find one) and I'll tell you where the testers went wrong.

Nobody suggested *not* adding the 64 MB. If you accept that PC100 = PC 133 (for all practical purposes) then logic would suggest 192 is better than 128.

sorry about hijacking this webdziner, but this RAM myth does need to be debunked.

Listening

http://www.tomshardware.com/mainboard/01q1/010104/amd-133fsb-07.html

This article clearly shows an improvement in performance between an A7V motherboard using PC100 SDRAM and an A7V133 using PC133.

pjknibbs, good example :-)

Sysmark scores: 219-215 = 4 (that's .0186 of a difference, or less than 2%!)overall.

Further, the A7V and A7V133 are substantially different. One uses the KT133 chipset and the other uses the vastly superior KT133A chipset. One is 200 FSB, the other 266 FSB, one uses B series and the other uses C series of Athlon processors. And the 686B Southbridge on the KT133A mobo gives considerable boost to the IDE subsystem.

So the 1.8% improvement here is almost all from the improved KT133A chipset, and almost nothing from the RAM.

Now, if Tom had only tried both the PC100 and PC133 in the A7V133......

Experts, I got your comments I put in the 64MB PC100 chipset and it is compatible but I have since took it out and purchased another 128MB of PC133 of SDRAM now I have another problem:  The system will not recognize the new 128MB of RAM.  I have physically removed the two chipsets and tried different physical configurations but the system still will not recognize the new memory.  I went under Add New Hardware and installed the Flash Memory 1 driver but still no recognization.  I went to the website of K-ByteMemory and tried to look for drivers but there were none and I saw memory configurators but the brand of computer wasn't there.  The brand of computer I have is a rebuilt one with no name but the monitor is KDS.  There is a website for KDS but no mention of memory.  How do I get the system to recognize the new memory?  The amount of memory now in the system shows 120MB.  

Thank you.  
David
P.S. Thank you for your comments

it could very well be that the memory is unsupported by your motherboard, the motherboard is what you go by for reference. I forgot what the voltage was for SRAM possibly 3.3v ? but anyhow, first try to see who manufactures your motherboard and what model is it. ocasionally you can run across ram that is incompatible with your pc. for reliablity, price and compatibility i would choose PNY for ram/video cards and so on. micron, kingston or crucial is also good.
find out what motherboard you have and then if you're sure the ram you bought is incompatible, sell it on ebay or to someone that u know who needs ram. the manufacurer of the ram should tell what it's compatibilities are.

...... also, you shouldn't have to install a driver for memory, memory is like USB--plug n play. it should automatically work as soon as u plug it in, your motherboard's BIOS is what detects it, accepts it etc.

Thank you jack902902 for the good information.  I will try what you said.