What do the numbers on a hynix memory mean

[rayrainer1]

I have a Mac Pro mid 2010 computer. I have been told that it is difficult to just add one memory module, unless you can find the exact memory. I have gotten close, except for the "C" and "1033" at the end. The memory I found says H9 to AB 1030 was the closest so far at the end but the "C" is missing and not the same last number. I don't know how important those different numbers are to match them perfectly. I don't use Macs that much anymore but picked this up fairly cheap a while ago.

Memory currently in the Mac Pro mid 2010

hynix 2gb 2rx8 pc3-10600e 9 - 10 - e0
HMT125U7TFR8C - H9 to AB - C 1033

Memory that is close:

hynix 2gb 2rx8 pc3-10600e 9 - 10 - e0
HMT125U7TFR8C - H9 to AB 1030

 

[brispuss]

The "C" is not so important.

There is no guarantee of inter-module compatibility by using another memory module even with the exact same part number/labeling as an existing memory module. Using another memory module with (slightly) different part number/labeling further reduces the chances of inter-module compatibility.

Two choices -

1) Try other modules with as close as possible part number/labeling as the existing modules until an inter-module compatible combination is found. But be prepared to spend more time and money on additional modules until a compatible combination is found.

2) Get a 2 x 2 GB dual channel kit to replace the existing memory. The modules within the kit have been tested and are guaranteed to be compatible with each other. This option usually saves time and money in the end. The existing memory modules could be kept as back up, or sell them.

Option 2 is the preferred one.

 

[rayrainer1]

Then I would have to get 4 x 2gb in order to get the 8 gig I want, since the 2 x 2gb memory left in there might not be compatible with another pair that is not the same, if I were to leave a pair in there along with another pair, from what I understand.

 

[brispuss]

Correct.

If wanting 8 GB total memory, then ideally a 2 x 4 GB dual channel kit should be used IF the system supports 4 GB memory modules. Failing that then a 4 x 2 GB quad channel kit should be used instead.

 

[rayrainer1]

Correct.

If wanting 8 GB total memory, then ideally a 2 x 4 GB dual channel kit should be used IF the system supports 4 GB memory modules. Failing that then a 4 x 2 GB quad channel kit should be used instead.

I took a chance and bought a used Hynix 2gb memory for $9.62 with almost the same exact info, except for the last 4 numbers. I thought I was either going to save some money or waste it but it seems to work fine. I guess those 4 numbers must not be too important: What encouraged me to buy it was someone was selling 4 x 2gb hynix where 3 of the sticks were the same but the 4th one had the 4 different last numbers. Not that it meant those would work but it was encouraging.

I bought this below where mine said 1033.

hynix 2gb 2rx8 pc3-10600e 9 - 10 - e0
HMT125U7TFR8C - H9 to AB - C 1109

 

[brispuss]

Fortunate in that the "new" memory module works with other individual modules.

The last four digits within the characters printed on labels indicate when the modules were manufactured. But even if you get another memory module with the exact same date of manufacture, there is still no guarantee that it would work compatibly with an existing memory module with the same manufacturing date.

 

[ranadeep_h]

Thanks Brispuss. That was a very helpful piece of information. High five !