MP 1,1-5,1 1866mhz DDR3 RAM OK in 5,1?

[judino28]

I ordered a 24gb Ram upgrade kit from OWC for my 3.33 six core 5,1. It was clearly the 5,1 kit when ordered. Installed it today and no issues. But, upon close inspection, I noted that the modules they sent me were for an 24gb 1866mhz upgrade kit for a 2013 6,1. They are Samsung 8gb 1Rx4 PC3-14900R modules that also have an OWC sticker and came in OWC packaging. OWC is investigating the error and will get back to me tomorrow with an update regarding refund or whatever.

In system profiler, they correctly show up as the full 24gb running at 1333mhz ddr3 and, again, all seems to work flawlessly.

Should I be concerned and/or is performance going to be impacted negatively in any way?

 

[SteveManila1960]

It will be fine the RAM will just run at the clock speed of your device i.e. 1333mhz. No harm done and no negative impact on performance it's just that the RAM will not be operating at it's intended speed.

 

[judino28]

That's good to know. "14900R" looks like it means it's ECC-Registered RAM. My previous RAM was not registered and I purposely was trying to avoid Registered as I seem to recall reading somewhere that ECC-registered (buffered) RAM may perform slower and ECC non-registered (unbuffered) in a 5,1. Any truth to that? I can't seem to find where I read that now and a quick search doesn't find anything specific 5,1 performance in this regard.

 

[SteveManila1960]

I am no expert here but I doubt it makes much difference. ECC registered RAM offers better stability and reliability but may have some latency. Whether it is noticeable or not I don't know. With respect, given the age of your computer I think this is probably the least of your concerns with regard to performance.