Two different RAM sizes and frequencies are not advisable?

[SHENGTON]

Hi Computer Hope Experts, good day.

I asked my friend last week about memory. I asked him if it's ok if I can mix two different RAM sizes and frequencies in my motherboard. He answered NO because it can cause damage or burn to my memory and every gold contacts in the memory has its own voltage. He said also that the gold contacts will turn to black. Not all contacts but some contacts will turn black color it's because mixing two different sizes and frequencies can cause burn to my memory.

Questions:
1. Is it true that mixing two different sizes and frequencies can cause damage or burn to my memory? and Why?
2. Two different RAM sizes and frequencies are not advisable?

[homer]

1. no
2. mixing RAM with different frequencies is not advisable due to the fact that the motherboard will simply go with the speed of the slowest RAM stick. mixing RAM sizes is ok as long as the two different RAM sticks have the same frequency and timings.

[SHENGTON]

Hello Si Homer, good day.

Thanks Sir homer.

Questions:

mixing RAM sizes is ok as long as the two different RAM sticks have the same frequency and timings.

1. I have two same RAM sizes here 256MB and they have different frequencies. What will happen if they have different frequencies and timings?

I use these two RAMs for almost 3 years now. And they still work well.

mixing RAM with different frequencies is not advisable due to the fact that the motherboard will simply go with the speed of the slowest RAM stick.

2. If I will install two different frequencies, the memory controller will set each memory to the lowest dominator of speed. In short it will down clock to the lowest frequency. What's wrong with that Sir if it will down clock to the lowest speed?

Thanks for the quick reply Sir Homer.

[homer]

1. answered in number 2

What's wrong with that Sir if it will down clock to the lowest speed?

2. nothing is wrong with it, its just the fact that you will not be using the faster RAM to its fullest potential. you payed more for faster RAM only to have it go as fast as the slowest RAM module.

[SHENGTON]

Some computer technicians here in our country they always advice to their customers not to mix two different frequencies? My instructor also said that to me not to mix different frequencies because it will cause damage/burn to my memory or memory contacts.

I'm thinking that my instructor isn't reading information in the internet and books. I'm thinking that my instructor and some computer technicians they are just basing it in their experienced.

Can you give me some links that will prove that my instructor and the computer technicians are not right?

[dslgeek]

This thread has more urban legend rather than fact. 
It is better to pay attention to the documentation. 
If you want more memory, and if it works, it is a good choice. 

[homer]

Can you give me some links that will prove that my instructor and the computer technicians are not right?

the computer technicians are right to advise not to mix RAM with two different frequencies (read my last post for the reason why), but i highly doubt the validity of your instructors claim. i cannot, however, supply any links to disprove his theory because i dont think it has ever happened. its like trying to find a link to disprove someones theory that if you pour water in your PCI slot a tree will grow out of it. i believe your instructor may have had a problem with damaged RAM and came to the incorrect conclusion that it was because they were different frequencies.

[patio]

In my experience it has never been a worthwhile endeavor to prove an Instructer wrong...
Best to leave sleeping dogs lie i say.

[SHENGTON]

Thanks guys, your inputs really helps.