hi, all: My computer has a PC2100 256mb memory in it, now, I want to buy a PC3200 512MB and add it into my pc, is that ok for PC2100 and PC3200 working together? I dont care both of them r working on PC2100 standard. thanks

Computer memory of the same type DDR, SDRAM, are built in batches. They are tested to meet certain standards. If they fail to meet the highest standard, they are tested for lesser standards. If reliable at the lower standards, they are sold as such.Generally, the higher standard RAM will have no problem with the slower speed busses. Mixing and matching is an on-going problem. Some computer MOBOs have trouble with unmatched RAM sticks. It usually is a problem when the same RAM stick speed/size are not matched but can occur with differing RAM stick speed/sizes are used. There are also powersupply and heat related issues the more RAM is installed in a computer.On a case by case basis, you will just have to buy the RAM and see if you have any problems. At the outset, you probably will not have any problem with the higher speed RAM operating correctly and you still will gain 256MB over the amount you had initially or you have a total of 768MB running correctly.W. Sieffert

I would expect that to work just fine, as long as you do not raise the memory clock, but continue running within PC2100 specs :-)

Well mixing ram even if they where both rated 2100 or 3200 is always a gamble. They don

In theory, they should work together no problem, but as others have mentioned, there can be exceptions...Some sticks just don't get along with others...But of you add 3200 to 2100, you will be limited to 2100 speeds. If you need the faster speed, you will have to dump the 2100 ram. I've got the same problem.. I really could use 3200 instead of the 2700 I have now. But to take advantage of the higher speeds, I'll have to dump my 2700 stick. The 3200 sticks will not help the 2700 work any better than it does alone. You will always be stuck to the speed of your lowest rated ram if you mix them. I had pc100 and pc133 mixed in my old cel box, and had no problems. But the speed was limited to the original pc100 ram being I didn't take it out. MK