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I recently bought 4 x 4GB 800 MHZ modules, but only 2 are recognized as 4GB the other 2 shows as 2GB but all at 667MHZ when it should be 800MHZ, can any one tell me what the issue is?
Thanks
S Robles
Los Angeles, CA
Mac Pro, OS X Yosemite (10.10.2)
What is specs on the new memory?
Do they have heatsinks?
Do you have a 2006/2007 Mac Pro?
How many memory slots?
Do you have other memory installed too?
If so what specs?
Are all the new memory identical as far as you can see?
What happens when you switch sticks does the indications change with moving the sticks?
I have a Early 2008 PAC Pro, yes they do have heatsinks. 8 Memory Slots which I can upgrade up to 32GB RAM.
Wherever I move the 4GB modules they still read as 2GB. But they are Bran New of the box.
Send them back. If new RAM - by itself - does not work - the set should be returned.
If any one DIMM is 667 then they all will have to downclock
Komputerbay 8GB (2x 4GB) DDR2 PC2-6400F 800MHz ECC Fully Buffered FB-DIMM (240 PIN) 8 GB w/ Heatspreaders for Apple computers
http://www.amazon.com/Komputerbay-PC2-6400F-Buffered-Heatspreaders-computers/dp/ B005HIWDBE/
Not sure about that brand Komputerbay $89 2x4GB
Otherwise, 667Mhz is much cheaper and works just fine in a 2008 3,1 along with filling all 8 DIMM slots works to improve performance so much so that even the small 4% difference is not a factor and you come out ahead.
I use these: 8 x 2GB $92
http://www.amazon.com/BUFFERED-PC2-5300-FB-DIMM-Arch-Memory/dp/B002ORUUAC/
Cheapest I have seen, might need to set the fans to 900 rpm
http://www.amazon.com/667MHz-Buffered-FB-DIMM-Memory-MA356LL/dp/B00D6Q45BA/
32GB for $280
http://www.amazon.com/gp/offer-listing/B009HNJCT6/
4 x 4GB $160
http://www.amazon.com/Buffered-PC2-5300-667MHz-FBDIMM-Memory/dp/B00S1Y0RSW/
You were sold a set and they are not what they were suppose to be and there is no quick fix other than to replace and have a correct set sent out.
What do you mean by downclock? I heard that term before. How about the 667MHZ recognition, is it because the machine originally had 667MHZ modules and now I decide to use the recommended 800MHZ - it does not recognized them as 800MHZ? Can the Risers be reset somehow to be able to recognize the 800MHZ, if so How do I reset them.
Thanks
you can reset the SMC.
If any RAM is present - now, not in the past - IS 667 then ALL RAM must try to run with the slower common denominator.
They. Are. Defective. At least some. And you should not have to do anything other than RMA them back to the vendor or cut your loss and try with one good set you have and supplement that. I would buy 6x2GB to fill all slots.
RAM not being recognized what it should.
