Jump to content
Sign in to follow this  
itsvince725

G4 MDD (FireWire 800) Doesn't Recognize All Its RAM

Recommended Posts

My G4 MDD (the FireWire 800 model with dual 1.25GHz CPUs) doesn't recognize all of its RAM. It has 4 512MB sticks installed but About This Mac only shows 1.75GB. I even pulled and reinstalled all the RAM. Could it be some kind of software issue? I'm running OS X 10.4.11.

 

It doesn't seem like bad RAM to me, because why would half a RAM stick be working and the other half not? I notice DIMM 2 shows up under System Profiler as being only 256MB, but it's clearly marked 512MB.

Edited by itsvince725

Share this post


Link to post
Share on other sites

Some MDDs are unhappy with high density 512mb RAM. Depending on the specifics, HD512s may ether not show up at all or read at half capacity.

 

When you're buying Mac RAM, it's almost always a good idea to buy low density RAM. Non-ECC LD RAM will have 16 chips total(8 per side) while HD generally has 8 chips. The LD rule is pretty much universally true when you're installing the largest size modules that a particular computer will recognize.

Share this post


Link to post
Share on other sites

All four RAM sticks are exactly the same (NewerRAM 512MB), they came installed in the machine when I got it.

 

Swapping each pair of RAM sticks moved the "half-size" stick to DIMM0. How do I count the DIMM slots anyway? Relative to the CPU assembly, is DIMM 0 the closest or the furthest away?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×