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For years, I have been predicting that Low-Power DDR (LPDDR) devices would make the crossover from mobile devices into laptops.

That prediction came true last year when a MacBook Air was introduced that .

I recently purchased a fairly powerful Windows 8 laptop for home use and I was surprised to see on the shipping label that it was purported to contain 8GBytes of LPDDR3 SDRAM, as you can see in the above photo (manufacturer¡¯s name obscured for reasons that will become clear later).

After having contributed to the LPDDR standards at JEDEC for years and predicting their arrival in laptops for some time, I was pretty excited to become the second person in my household to own a device containing LPDDR3. In fact, the 4th generation Intel Core (TM) processor in my laptop does support LPDDR3 devices, 

Alas, it was a little too good to be true. Digging in to the laptop¡¯s service and maintenance manual, I found that the memory in my new laptop was actually DDR3L and not LPDDR3. I¡¯m sure it was an honest mistake on the part of the laptop manufacturer and not an intent to mislead anyone; I am probably one of a handful of people in the world where the kind of memory inside would influence my purchasing decision. It¡¯s also partly true; DDR3L is a lower-voltage (and thus lower power) version of DDR3, but the term ¡°LPDDR3¡å refers to a specific DRAM implementation that is not DDR3.

So what¡¯s the difference between DDR3, DDR3L and LPDDR3? I get that question a lot, and there are a lot of differences. I have summarized some of the key differences in the table below. The short summary is, LPDDR3 is more expensive but has much lower standby power and a better form factor for mobile devices; while DDR3 and DDR3L are less expensive and consume more power but are more suitable for larger memory arrays found in PCs and servers.

How¡¯s the laptop? Great, I love it. It replaces an aging desktop, so the use model is similar to the old desktop, but with the added benefit of being more portable around the house. I¡¯ve seen people carrying around 17¡± laptops before I didn¡¯t appreciate how big it really is until I owned one. It¡¯s got a giant battery and it¡¯s never far from a power socket, so I don¡¯t miss the power savings from LPDDR3 at all in this laptop, but I will definitely be looking for LPDDR3 or LPDDR4 in my next mobile device purchases.