Some RAM questions

1. Depends on your motherboard, does it have support for Flex Memory Mode? If so it can run 2 sticks in dual single channel & 1 stick in single channel. If not it will run each in single channel.

2. It should scale back to dual channel if using 2 sticks on a triple channel mobo.

Also you should also always use sticks that have identical timings or it will default to the slowest speed. Ideally you would also want the same sticks, and even more ideally you would want a kit that is labeled as working in the specific channel mode you are looking for. But it generally works even if different sticks, as long as timings are the same.

zentro wrote: ↑1. Depends on your motherboard, does it have support for Flex Memory Mode? If so it can run 2 sticks in dual single channel & 1 stick in single channel. If not it will run each in single channel.

2. It should scale back to dual channel if using 2 sticks on a triple channel mobo.

Also you should also always use sticks that have identical timings or it will default to the slowest speed. Ideally you would also want the same sticks, and even more ideally you would want a kit that is labeled as working in the specific channel mode you are looking for. But it generally works even if different sticks, as long as timings are the same.

I just don't know if it'll be a net gain. The GD65 board has four DIMM slots, currently has 2x4gb DDR3-1600 9-9-9-24. The 3rd DIMM I'd like to install is same brand and same size as the other DIMMs, but different model (my existing RAM discontinued) and different timings (existing RAM is 9-9-9-24, new is CL11, doesn't say that whole hyphenated number). I want a net gain.

For performance it might be a downgrade speed wise, for capacity it will be an upgrade (meaning you could open more applications/use more ram).

If you are constantly running out of RAM then upgrade, if not then maybe don't.

RAM speed is only noticeable during certain times, like video encoding, gaming (to a certain extent, couple of fps difference unless you use an APU), anything to do with heavy calculations (unzipping files, etc).

If you already have the stick, do some benchmarks beforehand, then pop it in, then do another set of benchmarks and compare.

zentro wrote: ↑1. Depends on your motherboard, does it have support for Flex Memory Mode? If so it can run 2 sticks in dual single channel & 1 stick in single channel. If not it will run each in single channel.

2. It should scale back to dual channel if using 2 sticks on a triple channel mobo.

Also you should also always use sticks that have identical timings or it will default to the slowest speed. Ideally you would also want the same sticks, and even more ideally you would want a kit that is labeled as working in the specific channel mode you are looking for. But it generally works even if different sticks, as long as timings are the same.

I too have this problem. I'm picking up a desktop with 4 + 2 GB RAM. I know 6 GB RAM is enough for my purpose and needs.

Seems like it will operate the first 4 GB in dual channel mode as long as I put the 4 GB in one channel and the 2 GB in the second channel because doing so will put the system in Flex Mode.

Just check the guide and on page 62, it does say the small form factor desktop comes with flex mode. It definitely doesn't support triple channel.
http://h20628.www2.hp.com/km-ext/kmcsdi ... 9098-1.pdf

The system will operate in single channel mode if the DIMM sockets are populated in one
channel only.

The system will operate in a higher-performing dual channel mode if the total memory capacity
of the DIMMs in Channel A is equal to the total memory capacity of the DIMMs in Channel B.
The technology and device width can vary between the channels. For example, if Channel A is
populated with two 1-GB DIMMs and Channel B is populated with one 2-GB DIMM, the system
will operate in dual channel mode.

The system will operate in flex mode if the total memory capacity of the DIMMs in Channel A is
not equal to the total memory capacity of the DIMMs in Channel B. In flex mode, the channel
populated with the least amount of memory describes the total amount of memory assigned to
dual channel and the remainder is assigned to single channel. For optimal speed, the channels
should be balanced so that the largest amount of memory is spread between the two channels.
If one channel will have more memory than the other, the larger amount should be assigned to
Channel A. For example, if you are populating the sockets with one 2-GB DIMM, and three 1-GB
DIMMs, Channel A should be populated with the 2-GB DIMM and one 1-GB DIMM, and Channel
B should be populated with the other two 1-GB DIMMs. With this configuration, 4-GB will run as
dual channel and 1-GB will run as single channel.

Seems dual channel mode is a good thing to have:
http://www.computerhope.com/jargon/d/du ... memory.htm
http://acer.custhelp.com/app/answers/de ... -memory%3F