Combining 4 Sticks Of DDR3 RAM - Beneficial?

[tobe21]

So I currently have 2X4GB RAM installed in my PC, however I have just been given two 2X2GB sticks at no cost and am wondering if it would be beneficial to add them to my current setup.
As I understand it my motherboard supports Dual Channel RAM, however the RAMs are of different capacities and frequencies, so I am wondering if I add the new RAM sticks to slots 2 and 4 will it have a positive or negative effect on my current setup?

Current PC Specs
ASRock B75 Pro3-M
Intel i5-3470 Processor 3.2 GHz
Corsair 8gb DDR3 1600mhz
Samsung 128GB SSD
NVIDIA GeForce GTX 780 Ti (Galaxy Founders Edition)
Corsair CX650M (CP-9020103-AU) 650Watt 80Plus Bronze
Windows 10

Proposed (Additional) Ram Specs
Memory Speed: 1066 MHz
Memory Specification Compliance: PC3-8500
Features: unbuffered
Configuration Features: 2 x 2 GB
Technology: DDR3 SDRAM
Installed Size: 4 GB
Data Integrity Check: non-ECC
Rated Memory Speed: 1066 MHz

Further Helpful Links
Motherboard Information
Old RAM (taken from an Acer Aspire M3800)

 

[Lipex33]

I've just read your motherboard technical book and there you can find at page 20. "This motherboard also allows you to install four DDR3 DIMMs
for dual channel configuration, please install
""identical""
DDR3 DIMMs in all four
slots."
But you can give it a try because it may work if you put them. I have an Intel Q67 Motherboard Socket 1155 with 4 slots of ram and on 2 slots i have 1600mhz ddr3 and on the other 2 i have 1333mhz ddr3 and works fine.

 

[tobe21]

I've just read your motherboard technical book and there you can find at page 20. "This motherboard also allows you to install four DDR3 DIMMs
for dual channel configuration, please install
""identical""
DDR3 DIMMs in all four
slots."
But you can give it a try because it may work if you put them. I have an Intel Q67 Motherboard Socket 1155 with 4 slots of ram and on 2 slots i have 1600mhz ddr3 and on the other 2 i have 1333mhz ddr3 and works fine.

Thanks Lipex, do you know if it slowed your RAM's speed down to 1333MHz for all four sticks? Also was there a specific configuration to allow the same RAM to run through the same channel?

 

[Lipex33]

Yes they all work at 1333 mhz. Always when u combine rams they will always work at the lower speed on any motherboard. I have no config... i just put them in and started the PC. On slot 1 and 3 i put 2 x 4gb 1333mhz and on slot 2 and 4 i put 2 x 4gb 1600mhz.

 

[tobe21]

Yes they all work at 1333 mhz. Always when u combine rams they will always work at the lower speed on any motherboard. I have no config... i just put them in and started the PC. On slot 1 and 3 i put 2 x 4gb 1333mhz and on slot 2 and 4 i put 2 x 4gb 1600mhz.

Thanks fo the detailed explanation of your setup. I will implement accordingly and run some testing.