N40L and N54L were the first two Turion II Neo models launched in April 2010 together with a mix of Atlhon II Neo, Athlon II XLT and Phenom II XLT microprocessors. Main difference of these and other embedded Turion Neo CPUs from mobile Turion IIs is the same or lower power consumption, and smaller/thinner BGA package. Internal features of these Neo parts are not different from Turion II models: two CPU cores with 128 KB L1 cache and 1 MB L2 cache per core, wider 128-bit FPU path, support for DDR3 memory, and the same set of integrated technologies. The embedded Turions have some additional features, such as ability to work with low-voltage memory, or optional ECC memory support.
N40H and R40H are two Neo CPUs, that, we believe, were launched later than NxxL processors. Model numbers of these two microprocessors are similar to N40L and N54L, which is due to only one known difference between them: support for faster DDR3 memory. "L" series processors can support only DDR3-800, while newer "H" models may work with DDR3-133 memory.
Introduced together with the N40L, the M54L is clocked about 46% higher, i.e. at 2.2 GHz as opposed to 1.5 GHz for the Neo N40L. With the exception of TDP and, perhaps, core voltage and operating temperature, other features of processors are identical. Thermal Design Power of this model is 25 Watt, which is 10W higher than TDP of N40L.