CML8GX3M2A1866C9R Version Compatibility

[gandalfg8]

I've got a PC that was built about two years ago, using an i7-3770 CPU in an Asus Z77 Sabertooth motherboard with a CML8GX3M2A1866C9R 8GB memory set fitted and running Win7 Pro 64 bit.

I've just bought a new set of the same memory in order to increase the total to 16GB and was surprised to find that the new memory was version 3.24 whilst the original was version 8.16.

My first assumption was that the version number would be date related and came here just to find out whether or not this would matter. However, reading other posts with similar questions it now seems a lot more complicated than I was expecting, with it being suggested that different versions of the same part number are likely to be incompatible.

I've also seen the comments that memory sets are only warranted as tested, so theoretically adding another identical set even of the same version could be asking for trouble, but no reference was made to version numbers when I bought these and I'd appreciate any comments as to just how likely it is that I'm going to see any problems in practice.

I'm not looking to overclock the memory or anything else, I'm just looking for a stable system to handle some fairly heavy CPU loading and for the short time I've had the new memory installed all seems to be OK.

I've seen previous replies stating that supply voltages and other settings might need to be changed with more memory fitted but again I'm not sure if this applies anyway or just if overclocking.

[Technobeard]

There is no way to guarantee compatibility between memory that hasn't been tested together. Your best chance is if they're the same version number, but that doesn't guarantee compatibility. May work, may not. Yes, you may need to tweak the speed / timings / voltage to gain stability.

 

See the stickies. Version # = IC used.

[gandalfg8]

Thanks Technobeard for your response, I have seen the list of version numbers against IC used but that in itself means little to me other to make me wonder why something more obvious than a version number wasn't used to highlight these differences.

I've been working with IBM PCs and then clones for over 30 years but have never come across anything like this before.

This whole situation seems very odd, where products with the same part number from the same manufacturer and sold to the same specification can use different components and can also be considered to be potentially incompatible.

It might seem less silly if there was some more significant indication in the part number, an included suffix or something, rather than marking the modules with a version number that doesn't seem to get quoted when modules are offered for sale, although from what you say even using matching versions numbers still seems a bit hit and miss.

If it's expected these days that extending memory may lead to potential problems then I would at least have expected a requirement from manufacturers that retailers draw attention to this at the point of sale.

May work/may not doesn't seem very encouraging either, I could understand this if I was trying to tweak something for overclocking but not if I'm just asking one set of modules to meet it's published specifications alongside another of exactly the same part number.

The impression I'm getting so far is that if it's expected the end user may need to tweak speed/timings/voltage to gain stability then perhaps these products in their "off the shelf" state are already being pushed beyond comfortable limits to meet over optimistic published specification, in which case shouldn't there be at least a reduced specification made available to indicate at what limits supposedly matching parts can be guaranteed to co-exist?