DDR2 vs DDR3 on X200

The question seems obvious, but it isn't.

The model reviewed here on NBR on July 15th was equipped with 2Gb DDR2 667MHz memory.

When the X200 went up for sale, only DDR3 1067MHz options were available at Lenovo.

DDR2 so-dimms have 200 pins and DDR3 so-dimms have 204.

Therefore, DDR2 modules won't work on the X200... or will they?

What am I missing here? Was the model reviewed a month ago equipped with an altogether different motherboard from the ones being sold now? It seems very odd to think so... and yet backwards compatibility sounds odd as well.

Can someone shed any more light?

 

I didn't realise that DDR3 SODIMMs have 204 pins. Good to know I guess!

Anyway, the slots must be backwards compatible. The new intel chipset specifications list both DDR2 and DDR3 memory as compatible. There is no way that Lenovo is releasing different sets of hardware with some only compatible with DDR2 and some with DDR3.

 

That's true, and good to know. Thanks!

 

Now I'm not so sure...I've been doing some reading and everything seems to say that there is no compatibility between DDR2/DDR3 sodimms

 

DDRR2 is not compatible with DDR3. It is the same thing as DDR not been compatible with DDR2. It has a different pin count and I think it also has different voltage requiremens.

 

An idea is to look up the motherboard and see what it supports. It should give a list of ram speeds and sizes.

 

DDR3 and DDR2 will not fit in the same slot.. they have a different pin count, and the notch is in a different place so it is physically impossible to fit it them in the same slot.

I believe the answer is that the Intel chipset has the circuitry that supports both types of RAM, but laptop manufacturers can choose to either have the DDR2 slots or the DDR3 slots installed.

Seeing how DDR2 and DDR3 are both supported in the specs, and that they are incompatible with each other, I would say that this is probably the only possible answer

 

I would normally assume that NBR and CNET as well as others are capable of noting the correct RAM before conducting a review, but it would be very odd for Lenovo to send out units with a completely different motherboard (and therefore a different RAM) if they were looking to get an accurate evaluation of battery life and performance for units similar to the anticipated launch units. I'm not saying that NBR and CNET didn't check, I'm just saying that would be odd. I am interested in hearing if the NBR reviewer opened up the case to look.

 

Okay let me clear up everyone's confusion:

Montevina is a chipset. It is possible to make a chipset that handles two types of memory. Back in the day we saw motherboards with EDO and SD slots, but only one type could be used, motherbaords with SD and DDR, motherboards with DDR and DDR2. Same cases for them all. The chipset was able to address the different types of memory as long as there was a place for the memory to physically fit. The newest intel chipset supports DDR2 and DDR3 memory, but never at the same time. It will be on a case to case basis based on the motherboard manufacturer.

I hope this helps.

 

I totally get that, in fact my current desktop board handles both DDR and DDR2. What I don't get is whether or not this motherboard has 4 memory slots that would be user-accessible (2 DDR2 and 2DDR3). I understand you couldn't run DDR2 and DDR3 simultaneously, but I could max out RAM for much cheaper using DDR2 in two slots and then take them out and use DDR3 in the other slots once prices come down. I just never saw laptops that had that many slots on them to handle different types of RAM.

The tabbook doesn't show anything about DDR2 for the x200.

 

The x200 certainly does not have 4 slots for RAM. Mine has 2 (both user accessible with 2 screws) DDR3 slots. When ordering I tried (called on the phone and talked to 3 people) to get a model with DDR2 because you gain almost no performance with DDR3, but the substantially lower price would have allowed me to get 4 GB of DDR2 RAM in my machine. As it stands I have a single 2 GB DDR3 stick, and will upgrade it to 4GB when the price of DDR3 drops down to earth (I will not pay a 3-1 premium for DDR3 over DDR2).