[SOLVED] Help, about dual channel, bit buses,

[kaarelkostabi]

Long story short. All my knowledge comes from the internet. 1 of my gaming buddies went to a school, learned something about IT.
We got into an argument, he said you need to buy a kit of a ram to get dual channel working. Even if the serial numbers (or product ids or something) are different it doesnt work like it should. Something about bit buses if its not in a kit you'll get 64bit and if it is in a kit you'll get 128bit buses ?
He was telling it to someone that was building their first PC so i was like wtf are you even talking about. Match the mhz and cl and you're golden. It started when they showed their shopping cart and they had 2 identical ram sticks that were not in a kit.

 

[Eximo]

He's not wrong. Kits are guaranteed to work together, they have been tested at the factory and labeled accordingly then packaged.

You are also right in that you can get varying sticks of memory together and working. Just not as simple as plugging it in sometimes.

And 64/128, sort of. 64bit Bus communicating on the leading and trailing edge of the memory clock frequency. Early days of DDR they often advertised 128bits dual channel mode. It both is and isn't 128bit. DDR4 3200 is really running at 1600Mhz for example. All marketing numbers but there is truth behind it.

So in short, buying a kit, ideal. Buying multiple identical sticks, will probably work. However, you don't know if all the memory in the bin was made at the same time, so you could end up with similar, but not quite the same memory sticks, so there is a risk there. Mixing memory brands and all that, can certainly be done, but be prepared for issues, or having to manually set memory timings to something that all the sticks can handle, which can get weird.

 

[kaarelkostabi]

Even if the timings are identical, still means problems ?

 

[Eximo]

No guarantee, and advertised timings are not always exact. If you take a look at a memory settings on a high end motherboard, there are quite a few things you can change beyond the typical 16-18-18-20 or what have you. Also varying voltages.

But you are relying on SPD data for automatic settings, if they don't match it will just boot up at the default speed and timings for the memory controller. Hopefully that is acceptable to all the memory sticks in question.

Also OEM memory where they configure the SPD to only report back to certain motherboards. Apple memory for a common example, but HP has been known to do it on their modules as well.

 

[kaarelkostabi]

Ok, thanks