Want to increase my ram cap.

[ILosMasTeR]

I want to upgrade my ram capacity I got two 4 gb ram sticks should I buy one 8gb ram stick to increase it or two more 4 gb ram sticks to make it 4 x 4gb ram sticks ?

 

[inzane4all]

Buy in pairs if you can. CPU's run better in dual channel memory mode versus single.

 

[Barty1884]

I want to upgrade my ram capacity I got two 4 gb ram sticks should I buy one 8gb ram stick to increase it or two more 4 gb ram sticks to make it 4 x 4gb ram sticks ?

Potentially, although mixing & matching can be quite the crapshoot - there's just no guarantees.

Buy in pairs if you can. CPU's run better in dual channel memory mode versus single.

Dual channel does not necessarily 'require' only matching modules of the same speed.

Flex mode exists, to allow for "dual channel" using the 4GB portion of an 8GB module (as an example).
https://www.tomshardware.co.uk/ddr3-dram-faq,review-33220.html?_ga=2.247686983.1981130848.1538404518-183779354.1518709239#p7

Only 'works', if there's no stability issues from mixing & matching, timings, speed etc though, of course - and hardly the ideal route to go.

 

[Eximo]

It can actually be fully dual channel with 2x4GB + 1x8GB. The key is to have two equal sized memory banks. But that is very motherboard dependent from what I have seen.

 

[geofelt]

IF the ram sticks were compatible, then you could do either.
A single 8gb stick on one channel and the two 4gb sticks on the other would probably be as good as the 4 stick setup.
The problem is that ram must be matched.

Ram is sold in kits for a reason.
A motherboard must manage all the ram using the same specs of voltage, cas and speed.
The internal workings are designed for the capacity of the kit.
Ram from the same vendor and part number can be made up of differing manufacturing components over time.
Some motherboards, can be very sensitive to this.
This is more difficult when more sticks are involved.
That is why ram vendors will NOT support ram that is not bought in one kit.

If you do buy more disparate sticks, they must be the same speed, voltage and cas numbers.
Even then your chances of working are less than 100%

What is your plan "B" if the new stick/s do not work?

Sometimes increasing the ram voltage in the bios will make things work.

If you want 16gb, my suggestion is to buy a 2 x 8gb kit that matches your current specs.
Then, try adding in your old 8gb,
If it works, good; you now have extra ram.
If not, sell the old ram or keep it as a spare.