Memory Socket Configurations Socketts 3&4 Disadvantages

[JimMM]

I'm having issues trying to figure out what are the memory configurations ... there is so much conflict here in the forums and on the web about what slots to put my memory into.
MB GA-790XTA-UD4  AM3 Phenom2
Memory 2x2gb or 2x4gb 1600mhz

1st Question:  What is the disadvantage to putting my 2 sticks of memory into Slots 3&4 (white DDR3_3&DDR3_4) instead of slots 1&2 (blue) ?  ?  ?
...( the MemSlots are too close to my CPU cooler, so I can't use Slots 1&2(blue)

2nd Question:  Are Slots 1&2 Dual Channel Mode -OR- are Slots 1&3 Dual Channel Mode ?  ?  ?

3rd Question:   Is Ganged / UnGanged  determined by the Placement of the MemoryModules into the Dimm Slots ?    If so what is the configuration for UNGANGED

.... the manual states pg16 : It is recommended that you install 2 MemModules in DDR3_1 and DDR3_2

On the web  another person says for OverClocked Memory 1866mhz  only use slots 3&4

Another Web writer States that there are faster speeds to be had with 2 sticks of memory,  if you use all 4 slots the memory speed slows down (I think they said to the boards default)

per Dark Mantis    http://forum.giga-byte.co.uk/index.php/topic,2474.0.html
Reply #12 on: August 04, 2010, 01:05:14 pm » Sorry my bad. I was looking at the board and thought that the two sockets nearest the CPU were the dual channels. They should be seated in the two white slots for dual channel mode. The BIOS should autosense the modules as dual channel. Sounds like the board is faulty then. You will need to get it RMAed.

Another Gigabyte forum topic DarkMantis states  to install 2 DDR3 MemoryModules in Slots 1&3

WIKIpedia Dual Channel Memory    http://en.wikipedia.org/wiki/Dual-channel_architecture
The memory modules are installed into matching banks, which are usually color coded on the motherboard. These separate channels allow each memory module access to the memory controller, increasing throughput bandwidth. ... If the motherboard has two pairs of differently colored DIMM sockets (the colors indicate which bank they belong to, bank 0 or bank 1), then one can place a matched pair of memory modules in bank 0, but a different-capacity pair of modules in bank 1, as long as they are of the same speed.

[F5BJR]

*
My response is stupid but

Solution 1 = change your 2 * sticks of memory if possible by model less high  !!

Solution 2 = change your CPU cooler !!

Pierre

[bytheway_r]

1st Question:  What is the disadvantage to putting my 2 sticks of memory into Slots 3&4 (white DDR3_3&DDR3_4) instead of slots 1&2 (blue) ?  ?  ?

I don't think there's any disadvantage to using the white slots instead of blue. In the end, they're all supposed to run the same.

2nd Question:  Are Slots 1&2 Dual Channel Mode -OR- are Slots 1&3 Dual Channel Mode ?  ?  ?

Dual channel slots are color coded so white ( 1&2 ) are dual channel and 3&4, too.

3rd Question:   Is Ganged / UnGanged  determined by the Placement of the MemoryModules into the Dimm Slots ?    If so what is the configuration for UNGANGED

This is determined by bios settings. By default your memory should be set to unganged.

.... the manual states pg16 : It is recommended that you install 2 MemModules in DDR3_1 and DDR3_2

Indeed, though I'd assume it's just a precaution against compatibility issues.

On the web  another person says for OverClocked Memory 1866mhz  only use slots 3&4

I seriously doubt you'd see any overclocking difference between the slots. Word of caution, if you don't have a Thuban ( x6 ) CPU I'd stay away from 1866Mhz speeds. Even with Thuban you're risking your memory controller with anything above 1333Mhz ( it should be fine with 1600Mhz but it's still a risk ). Far as I know, 1866Mhz with other Phenom II's is borderline maximum of what will run at all. The risk of damaging the memory controller is rather substantial.

Another Web writer States that there are faster speeds to be had with 2 sticks of memory,  if you use all 4 slots the memory speed slows down (I think they said to the boards default)

It's quite likely that with all 4 slots filled the default speed will be 1066Mhz. Generally, with all slots filled you're looking at a limited RAM overclock and higher voltages to run the same speeds / latencies. Myself, I have 3x2GB atm and there is a slight overclocking penalty compared to 2 sticks.

[Dark Mantis]

per Dark Mantis    http://forum.giga-byte.co.uk/index.php/topic,2474.0.html
Reply #12 on: August 04, 2010, 01:05:14 pm » Sorry my bad. I was looking at the board and thought that the two sockets nearest the CPU were the dual channels. They should be seated in the two white slots for dual channel mode. The BIOS should autosense the modules as dual channel. Sounds like the board is faulty then. You will need to get it RMAed.

The board you took my quote from was an entirely different board for an entirely different chipset as it was based on the Intel platform and the two are not at all the same.

[absic]

2nd Question:  Are Slots 1&2 Dual Channel Mode -OR- are Slots 1&3 Dual Channel Mode ?  ?  ?

Dual channel slots are color coded so white ( 1&2 ) are dual channel and 3&4, too.

Be careful as this isn't exactly correct. For example on the GA-890FXA-UD5 motherboard that I am running slots 1&3 or 2&4 are used for Dual Channel Memory configuration. The best advice here is to check the User's Manual which should tell you the correct slots to use for your particular motherboard.

With regard to using slots 3&4 for faster RAM modules runn3R posted this reply in another thread.

(...) Any idea why 3&4 need to be used for overclocking? (...)

Hi r0jj (Dom)

It appeared after many tests which we've done that these 2 slots are best to choose from when you want to have better stability and easier OC to 1800 MHz and higher speeds.

which can be found here: http://forum.giga-byte.co.uk/index.php/topic,2714.msg18447.html#msg18447