Ram installation/slots for G5

[redhatcode29]

hi guys.... can someone brief me of the ram installation for a G5 (Dual Core model, max is 16Gb ram)

currently i have four sticks (2 x 512GB [green arrow] and 2 x 256GB [pink arrow]) installed. however the total rams read up to only 1GB. If i leave only two 512 s installed, the reading shows as 512Gb.

(This pic is for illustration only)

All rams read as 256gb as shown below.

If i add more (tried 2x 512gb, 2x 1Gb, 2x 2Gb exactly paired), still, the total readings show as 1GB ram installed....worse, these extra fitted rams dont even show up in the memory slot in 'more info'.

i also tried with only 2x 2gbs..... upon turning on, the warning sound was followed by a wild spin of the fans. why does it read as 256gb for all sticks ?

i can brain it if the rams (512) are shown as 256 only....but the extra rams, that if i fit in more that the arrows shown..- that do not appear at a all....

How do install more rams and overcome this issue of rams not even appearing in the info section. Thanks

 

[MacCubed]

hi guys.... can someone brief me of the ram installation for a G5 (Dual Core model, max is 16Gb ram)

currently i have four sticks (2 x 512GB [green arrow] and 2 x 256GB [pink arrow]) installed. however the total rams read up to only 1GB. If i leave only two 512 s installed, the reading shows as 512Gb.

(This pic is for illustration only)
View attachment 602592


All rams read as 256gb as shown below.

View attachment 602593



If i add more (tried 2x 512gb, 2x 1Gb, 2x 2Gb exactly paired), still, the total readings show as 1GB ram installed....worse, these extra fitted rams dont even show up in the memory slot in 'more info'.

i also tried with only 2x 2gbs..... upon turning on, the warning sound was followed by a wild spin of the fans. why does it read as 256gb for all sticks ?

i can brain it if the rams (512) are shown as 256 only....but the extra rams, that if i fit in more that the arrows shown..- that do not appear at a all....

How do install more rams and overcome this issue of rams not even appearing in the info section. Thanks

The RAM needs to be paired. Install one of the 512MB sticks in the bottom slot in the top section, and install the other 512MB in the top slot in the bottom section. Then install the 256MB sticks in the second bottom slot in the top section, and the second slot on the top in the lower section.

 

[redhatcode29]

The RAM needs to be paired. Install one of the 512MB sticks in the bottom slot in the top section, and install the other 512MB in the top slot in the bottom section. Then install the 256MB sticks in the second bottom slot in the top section, and the second slot on the top in the lower section.

a mismatch ...ok, will try it out. thanks

 

[MacCubed]

a mismatch ...ok, will try it out. thanks

No problem, hope my explanation wasn't too confusing lol

 

[bunnspecial]

Swap the sticks around in ONE of the RAM banks and it should sort everything out.

When I install RAM in G5s, I always start with the two innermost slots and build outward. This is an easy way to keep things matched.

 

[eyoungren]

Swap the sticks around in ONE of the RAM banks and it should sort everything out.

When I install RAM in G5s, I always start with the two innermost slots and build outward. This is an easy way to keep things matched.

I go in the opposite direction. I build out to in. But I also haven't had to match ram in a G5 very much either.

Works out the same way though.

 

[MacCubed]

I go in to out, it seems more organized that way. I put the lower capacity sticks on the slots further to the center

 

[Hack5190]

I go in to out, it seems more organized that way. I put the lower capacity sticks on the slots further to the center

Doing some testing of memory modules I discovered that if you place (the correct type) of matched memory in the inner slots and mis-matched next the system will boot ignoring the mismatched (and any memory in slots beyond that). To me that means that the PPC reads memory from "in to out" (as MacCubed describes it).

 

[redhatcode29]

No problem, hope my explanation wasn't too confusing lol

nah...it wasn't. just had to read it twice. Thanks for your guide, i managed to place the rams in the correct position.

However i have an issue where my 512 sticks read 256. i also tried a different set of 512, still the same, tried some swapping her and there ...only got worse, so left it at this current setting with 7GB though it suppose to be 7.5gb.

i want to make it 8gb, it just won't let me do it!! thanks

 

[redhatcode29]

Swap the sticks around in ONE of the RAM banks and it should sort everything out.

When I install RAM in G5s, I always start with the two innermost slots and build outward. This is an easy way to keep things matched.

i believe this is the same method as maccubed.

 

[redhatcode29]

Doing some testing of memory modules I discovered that if you place (the correct type) of matched memory in the inner slots and mis-matched next the system will boot ignoring the mismatched (and any memory in slots beyond that). To me that means that the PPC reads memory from "in to out" (as MacCubed describes it).

when i mismatch.....the the warning sounds, won't boot.

 

[Hack5190]

Here is the memory info from the G5 service manual