Can i use two different types of DDR ram

[SadisticX89]

i have a Asus nforce 430 motherboard
with a AMD phenom 9550 2.2 quad

i currently have 4 gigs of DDR ram installed and my board can support up to 8 gigs of DDR 2.

so my question is can i upgrade another 4 gigs of DDR 2 ram as long as they are matched pairs and still run my previous 4 gigs of DDR as matched pairs at the same time. Or do i need to run all DDR or all DDR 2 for my system to run with no errors.

 

[treefrog07]

Your board supports up to 8GB of DDR2 800MHz RAM. You can add 2 x 2GB DDR2 800MHz RAM. Try to match the existing RAM's speed (MHz) and latencies, eg., 5-5-5-15 (it should be on the stickers of your existing RAM). Before you install the new RAM, you should open the BIOS and increase the northbridge voltage one or two increments higher then the default value.
p.s., if you are using a 32-bit (x86) version of windows, your system will not be able to see or use more than ~3.5GB of memory - you have to use a x64 windows system to use all 8GBs of RAM.

 

[SadisticX89]

Ok i actually just found out im currently running 4 gigs of ddr 2 at 800 mhz so ill add another 4 of the same type. I am actually running a 32 bit version of xp but before i install the new ram i will have a 64 bit version of 7 thanks for your help and reply treefrog. Only part im unsure of is increasing the voltage in the bios. Never done any work in there myself, but have friends that can. Is it normally recommended to increase the northbridge voltage when upgrading ram on a custom built pc?

 

[jaquith]

To add to this, I would recommend that not only matching the speed, CAS, but to also make certain that the voltage is identical. The increase of voltage is not necessary but it can help if there's a failure or instability.

What exact part-number or link is to your DDR2 currently installed??

Next, input your current MOBO into the RAM Mfg site to search for similar Tested DDR2.

Example only - http://www.crucial.com/store/listparts.aspx?model=M2N

 

[treefrog07]

Ok i actually just found out im currently running 4 gigs of ddr 2 at 800 mhz so ill add another 4 of the same type. I am actually running a 32 bit version of xp but before i install the new ram i will have a 64 bit version of 7 thanks for your help and reply treefrog. Only part im unsure of is increasing the voltage in the bios. Never done any work in there myself, but have friends that can. Is it normally recommended to increase the northbridge voltage when upgrading ram on a custom built pc?

You're welcome. Increasing the northbridge voltage is to accommodate having all four RAM slots populated, most mfrs. assumed their customers would only use two sticks, and until the last couple of years, with the increasing popularity of 64-bit OSes, they were right. Your BIOS should allow you to access the northbridge voltage settings and change it. You should only need to increase one or two bumps higher than the default setting.

 

[jaquith]

A byproduct is higher temps.