Question between DDR3 and 3L

I understand L is Low power, but can I pair L with normal ram? At that would 1600 mhz and a 1333 mhz module make issues with each other?

My new laptop can use 16 GB of ram and I could make it 12, but it has DDR3L and I only have DDR3.

I wouldn't risk mixing them - unless of course you want some nice crispy memory for dinner.

Apparently, DDR3L can operate at both 1.35V or 1.5V, according to Dell.

if you have better hardware your mobo should be able to handle it.

My Lenovo T430s came from the factory with one stick DDR3 and one stick DDR3L. Both 1600mhz. Even two different brands. They do have different voltages, they do not both run on 1.5V.

So this would be a safe attempt?

On my notebook I have two DIMMs with the same frequencies and timings but they run one at 1.35v and the other at 1.5v. So I guess the safest bet is have same speeds and timings, the voltages are not that important. Those DIMMs where installed by HP itself so I guess this solution is made for the best stability (I've never had any issues).

So long as the laptop isnt one of those skylake botchlings, you should be fine with mixing the two. I was in a similar scenario when I picked up an alienware alpha; the computer came with 4GB DDR3L, and I had a 4GB stick of laptop mem I bought 6 years ago. From what I could tell, the computer will default with whatever JEDEC profile both sticks can agree on(1.5v @1333MHz with both sticks, vs 1.35v @1600MHz single 3L)