What is the PC3 on RAM? and which RAM?

Hello, I am upgrading the RAM of my Malibal Lotus Series (Sager NP8150) and I am on newegg.ca looking at RAM both 1333mhz and 1600mhz. I am a bit confused between the differences when it comes to the PC3 number. What is a PC3 number?

e.g.

On the Malibal website I customized my laptop with the following RAM: (8GB) 8192MB, PC3-10660/1333MHz DDR3. On Newegg.ca there are no RAM modules that say PC3-10660 only ones that say:

DDR3 1333 (PC3 10600)
DDR3 1333 (PC3 10666)
DDR3 1600 (PC3 12800)

What are the differences? Is there a certain one I would need to buy for my Intel® Core™ i7-2720QM, 6MB L3 Cache, 2.2-3.3GHz? i.e. is PC3 10600 not supported or some compatability issue regarding the PC3s?

Also on a side note when looking to buy RAM what factors do I need to consider besides the mhz? How much does 7 latency differ from 9 latency?

If I chose 1333mhz would this module work for an upgrade?

G.SKILL 8GB (2 x 4GB) 204-Pin DDR3 SO-DIMM DDR3 1333 (PC3 10600) Laptop Memory Model F3-10600CL9D-8GBSQ Newegg.ca - G.SKILL 8GB (2 x 4GB) 204-Pin DDR3 SO-DIMM DDR3 1333 (PC3 10600) Laptop Memory Model F3-10600CL9D-8GBSQ

and if I chose 1600mhz would this module work?

G.SKILL 8GB (2 x 4GB) 204-Pin DDR3 SO-DIMM DDR3 1600 (PC3 12800) Laptop Memory Model F3-12800CL9D-8GBSQ Newegg.ca - G.SKILL 8GB (2 x 4GB) 204-Pin DDR3 SO-DIMM DDR3 1600 (PC3 12800) Laptop Memory Model F3-12800CL9D-8GBSQ

EDIT: Is G.SKILL RAM good? Also there wouldn't be any compatibilty issues if 8GB of memory was PC3-10660 and the other 8GB was PC3 10600 or something other than PC3-10660?

 

Memory bandwidth - Wikipedia, the free encyclopedia

This may help. It's mostly just a JEDEC naming convention that depends on what yardstick you're using. Stick to either DDR3 naming or PC3 and you'll be fine. if you're not sure, divide/multiply by 8 and round a little.

 

Thanks for the link. So since 10600/8 = 1325 does that mean that the DDR3 1333mhz PC3 10600 is not actually 1333mhz but 1325mhz? So (and according to the Wikipedia article the mhz is the MAXIMUM not the average) its max mhz isn't even a full 1333mhz. I think I will go with the 1600mhz module instead.

 

Those are approximations. Don't expect the exact division.


--

 

Does that mean it might actually be 1333mhz?

 

Just as many manufacturers advertise their RAM as PC3-10666, in which case it would divide to give you approximately 1333MHz. Bottom line, it's simply a naming convention--RAM of the same standard specs will all run at the same speed.

The naming standard isn't crystal clear, so manufacturers, building off the consumer "bigger is better" tendency, alternatively names the RAM PC3-10600, PC3-10660, or PC3-10666.

 

So what do you think about the links to the RAM modules?

 

Faster rated RAM can always clock down to match your actual speed. Slower RAM usually will not. Typically, best bang for the buck with laptops comes from going with the cheapest option that is at least as fast as your minimum rating. I say that only because faster can sometimes be cheaper, depending on supply/demand and market forces.

 

Is G Skill a good brand? and those modules are compatible with my laptop?

 

Yeah, G Skill is a reputable brand and any DDR3 SODIMM will be compatible with your laptop. Mismatched RAM might not play nice together in rare cases though. i.e. having 2 kingston + 1 Corsair + 1 G Skill. I'd get RAM sticks of the same brand, aside from that any sticks from a reputable brand will do just fine.

 

G Skill with the brand that Malibal supplies. 8GB of memory from Malibal and 8GB from newegg.ca (which is G Skill).

 

You should be fine then, like i said it's rare that mismatched RAM doesn't play nice but it does happen. It never happened to me, but i've seen an instance where a Corsair SODIMM didn't play nice with 3 Kingston ones.

Usually as long as you have matching pairs you'll be fine, most problems i've seen came from trying to run two mismatched sticks in dual channel not mismatched pairs.