Ram upgrade causing errors

[Nsummers82]

Is the 2 x 2gig RAM the original RAM?

- Nick

Yes they are original

 

[Nsummers82]

Actually now that I'm looking at it the original ram has 8 smaller modules on the chip and the new compatible ones only have 4. Can it only use low high density chips?

 

[pigoo3]

Installed the new ram 2x4gb with the 2x2gb and same errors. Installed only the new 2x4gb and same errors. Put the original 2x2gb back in and it works perfectly.

Something is certainly not right. If the original RAM works fine...and the new RAM was purchased from Crucial or OWC...then one possible issue would be the RAM slots. To test this...install the "good" RAM (the original RAM) in all 4 RAM slots (multiple tests)...and see what happens.

- Nick

 

[ferrarr]

Do you have other devices plugged in to the iMac? Maybe try with everything disconnected from the iMac. Also an SMC reset might help.

 

[Nsummers82]

Tested that before and it works fine. I'm thinking that the ram with 4 modules on them are high density and this iMac is not compatable with that? The three sets I have tried have that in common and that is the ONLY difference when compared to the original ram.

 

[pigoo3]

I'm thinking that the ram with 4 modules on them are high density and this iMac is not compatable with that? The three sets I have tried have that in common and that is the ONLY difference when compared to the original ram.

I've seen all sorts of RAM module configurations (number of chips on the module). I would not automatically assume that because the modules look different...that they are different.

If this RAM was purchased from Crucial or OWC/macsales (I sure hope they were)...then they will work. I have never heard of someone having this much trouble with a RAM upgrade.

If this replacement RAM was not purchased from Crucial or OWC/macsales (suppliers that we trust)...then please order from them ASAP...and this issue will be a non-issue!

- Nick

 

[Nsummers82]

I've seen all sorts of RAM module configurations (number of chips on the module). I would not automatically assume that because the modules look different...that they are different.

If this RAM was purchased from Crucial or OWC/macsales (I sure hope they were)...then they will work. I have never heard of someone having this much trouble with a RAM upgrade.

If this replacement RAM was not purchased from Crucial or OWC/macsales (suppliers that we trust)...then please order from them ASAP...and this issue will be a non-issue!

- Nick

These we from Crucial. Recently I've been reading that high density ram can cause issues. And that is the only difference between the Crucial ram and the stock ram.

 

[pm-r]

These we from Crucial. Recently I've been reading that high density ram can cause issues. And that is the only difference between the Crucial ram and the stock ram.

Can it only use low high density chips?

That certainly seems logical, but a bit surprising for a 2010 Mac model. I thought Apple had that sorted that problem out by then.

Canadaram (a very reputable local Canadian dealer) doesn't say anything for that model about density, but does say this:
"Macintosh iMac intel i3 Mid 2010 and Late 2011 Edu models only DDR3 21.5" and 27" (DDR-3 1333 MHz SODIMM)
MC510LL/A, MC509LL/A, MC508LL/A, MC978LL/A Four sockets, supports up to 16GB (4x4GB) Bank 1 must be populated first. "
http://canadaram.com/apple_imac_intel.htm

Notice the part I set to bold for your model.





- Patrick
======

 

[Nsummers82]

That certainly seems logical, but a bit surprising for a 2010 Mac model. I thought Apple had that sorted that problem out by then.

Canadaram (a very reputable local Canadian dealer) doesn't say anything for that model about density, but does say this:
"Macintosh iMac intel i3 Mid 2010 and Late 2011 Edu models only DDR3 21.5" and 27" (DDR-3 1333 MHz SODIMM)
MC510LL/A, MC509LL/A, MC508LL/A, MC978LL/A Four sockets, supports up to 16GB (4x4GB) Bank 1 must be populated first. "
http://canadaram.com/apple_imac_intel.htm

Notice the part I set to bold for your model.





- Patrick
======

Is bank 1 monitor side or back side?

The iMac functions with the original ram in either bank. Errors when I add the new ram to either bank. And errors when I use only the new ram in either bank.

 

[pm-r]

Is bank 1 monitor side or back side?

I'm not sure but the System Info > Memory will show what's installed and where, when its booted.

I've never really looked to see if they are physically numbered by the RAM slots.

Apple doesn't really say from what I found:
https://support.apple.com/en-us/HT201191#2

But does say:
"Top" refers to the slots closest to the display; "bottom" refers to the slots closest to the stand.) "

 

[Nsummers82]

16gb (4x4gb) of low-density ram from OWC is arriving today. If I still have issues I don't know what else could be wrong.

 

[pigoo3]

16gb (4x4gb) of low-density ram from OWC is arriving today. If I still have issues I don't know what else could be wrong.

Hopefully this is what was ordered from OWC (macsales.com):

https://eshop.macsales.com/item/Other World Computing/1333DDR3S16S/

All this talk about low-density & high-density...etc. etc...only complicates things. Trusted websites like OWC and Crucial make purchasing RAM very easy (just look up the model computer & the purchaser is given the compatible RAM options). The terms "low density" and "high density" are not even mentioned in the link.

Just as an example of this. In the link above there's a choice to get 16gig of RAM via 2 x 8gig of RAM (versus 4 x 4gig of RAM). If the 2 x 8gig of RAM choice is clicked on...on the next page is clearly lists all computer models 2 x 8gig of RAM is compatible with.

On this page it clearly indicates that 2010 21" iMac's with an i3 CPU...are NOT compatible with the 2 x 8gig RAM choice:

https://eshop.macsales.com/item/Other World Computing/1333DDR3S16P/

This of course would have prevented what happened at the beginning of this thread.

Fingers crossed the soon to arrive RAM upgrade works. Normally RAM upgrades are very very easy...and are one of the simpliest hardware upgrades that can be performed. Please let us know how things go...we certainly want a happy ending to this story!

- Nick

 

[Nsummers82]

Hopefully this is what was ordered from OWC (macsales.com):

https://eshop.macsales.com/item/Other World Computing/1333DDR3S16S/

All this talk about low-density & high-density...etc. etc...only complicates things. Trusted websites like OWC and Crucial make purchasing RAM very easy (just look up the model computer & the purchaser is given the compatible RAM options). The terms "low density" and "high density" are not even mentioned in the link.

Just as an example of this. In the link above there's a choice to get 16gig of RAM via 2 x 8gig of RAM (versus 4 x 4gig of RAM). If the 2 x 8gig of RAM choice is clicked on...on the next page is clearly lists all computer models 2 x 8gig of RAM is compatible with.

On this page it clearly indicates that 2010 21" iMac's with an i3 CPU...are NOT compatible with the 2 x 8gig RAM choice:

https://eshop.macsales.com/item/Other World Computing/1333DDR3S16P/

This of course would have prevented what happened at the beginning of this thread.

Fingers crossed the soon to arrive RAM upgrade works. Normally RAM upgrades are very very easy...and are one of the simpliest hardware upgrades that can be performed. Please let us know how things go...we certainly want a happy ending to this story!

- Nick

Correct. That is exactly what was ordered this time.

As far as what happened in the beginning, that was my fault. I believed what I read on the Internet and knew better lol.

The replacement from Crucial of 2x4gb however should have worked but didn't. I can only attribute that to being high density ram. Odd, I know, but that was the only difference.

 

[pigoo3]

Correct. That is exactly what was ordered this time.

As far as what happened in the beginning, that was my fault. I believed what I read on the Internet and knew better lol.

The replacement from Crucial of 2x4gb however should have worked but didn't. I can only attribute that to being high density ram. Odd, I know, but that was the only difference.

By the time this RAM upgrade project is completed. You're going to know way more about RAM and 2010 iMac's than you EVER wanted to!

- Nick

 

[pm-r]

By the time this RAM upgrade project is completed. You're going to know way more about RAM and 2010 iMac's than you EVER wanted to!

- Nick

Only 53+ messages Nick.

There have been a lot worse…




- Patrick
======

 

[chscag]

It's going to be interesting to see if the OWC modules work OK. I would have thought that it did not make a difference if the modules were low or high density as that is determined by the module chips not the physical size or pin out of the module. A 2010 iMac should be able to use either low or high density modules. I'm fairly certain My 2013 iMac will use either - since I upgraded it several years ago with Crucial modules.

 

[pm-r]

I would have thought that it did not make a difference if the modules were low or high density as that is determined by the module chips not the physical size or pin out of the module.

I don't know if these change anything…

http://www.techrepublic.com/blog/us...-watch-for-high-and-low-density-requirements/

http://www.ebay.com/gds/MythBUSTED-...ity-vs-High-Density-/10000000003939852/g.html





- Patrick
======

 

[chscag]

I don't know if these change anything…

Informative, but they don't change a thing. I've seen many cases of memory modules not being compatible with certain PCs or Macs, but it usually is because the wrong memory was chosen. The belief that one can use fast memory in a machine that calls for slower memory is an example of incorrect memory. And yes, there are certain high density modules that may not be compatible but we're talking here about ordering from Crucial. If you give the correct information to Crucial about your Mac or PC, they will send memory that will work. Same goes for OWC.

 

[Nsummers82]

By the time this RAM upgrade project is completed. You're going to know way more about RAM and 2010 iMac's than you EVER wanted to!

- Nick

New OWC ram is working perfectly! Thanks everyone for the help.

 

[pigoo3]

Awesome!!!

- Nick