At the time I got my Mac Mini Duo my wife also got one of the Macbook Pro 2.0 (speed bumped 1.83 machines).

Both machines came with stock standard memory. ie. no memory upgrades.

After owning both for about 16 days or so, we decided to purchase a 1gb ddr2 chip for each one. Ordered from my preferred supplier as when I ordered an item from them previously that was DOA, it was swapped with very little fuss from the distributor. So with that in mind I knew if and when I ever have a problem they wont make my life difficult.

2 x 1gb ddr2 chips arrive next business day. Install one into my Mac Mini Duo and the other is installed into the Macbook Pro.

For the Mac Mini I removed one of the 256mb ddr2 chips and installed the 1gb ddr2 into dimm0, thus leaving dimm1 with the other 256mb ddr2 chip.

For the Macbook Pro I put the 1gb ddr2 into dimm1, and dimm0 contained the 512mb ddr2 factory chip.

Within hours of installing the memory into the Macbook Pro it managed to freeze the system. You could move the mouse when this happens, but you wouldn't be able to select applications or anything. You would see the beachball/spin wheel effect. You would also see that the system clock in the top right hand corner would be frozen in time when the freeze happened.

Mac Mini Duo produced no such problem.

Swapped order of dimms in Macbook Pro only to have the same problem again.

Removed the factory 512mb ddr2 and ran the 1gb ddr2 in dimm0 on its own. Once again same problem.

Swapped the 1gb ddr2 into dimm1 and ran it on its own again. Once again same problem.

Removed the 1gb ddr2 and installed the factory 512mb ddr2 back into dimm0.

Machine had no problems on factory chip previously, and the problems relating to freezing as above started only when the 1gb ddr2 started to be used (and was always in the machine in any situation).

Mac Mini Duo continues to run fine, no such problems with its configuration and/or 1gb ddr2 chip.

Apple Hardware Test ran on the Macbook Pro with either chip on its own or both together all show up as clean. The problem seems to follow the 1gb ddr2 and never happens in a certain dimm socket. Factory dimm never faults on its own.

Reinstalled the OS from scratch. Only installed enough patches to put me upto 10.4.6 and no further update after this. Installed the following applications so that my wife could atleast use the machine. Xchat, Adium, VLC etc.

By the time I did the reinstall I'd already been sent a replacement chip from the distributor, by arrangement of my supplier I bought the memory off.

Attempted to run the replacement 1gb ddr2 in the same configurations as above and each time it faulted in the same way. Exactly the same way and all the same configurations.

As of yesterday I was sent a 3rd dimm, this time directly from my supplier but this time a different brand they use from a different distributor.

Apple Hardware Test runs fine with 3rd 1gb ddr2 and factory 512mb ddr2.

Ran the system with both dimms overnight and it faulted as per previously. Rather then swap dimm order, I told my supplier I would run the new 1gb ddr2 on its own as I had seen people reporting that non matched dimms can certainly cause problems. So its possible that running the factory 512mb ddr2 (Hynix) with this other chip might not be possible.

Removed factory 512mb ddr2, placed 1gb ddr2 into dimm0 to run on its own.

It's currently been running for about 15 hours with no freeze in the above configuration.

The test will be the next 24-48 hours in this configuration, especially tonight. As the problem can happen anywhere from 4 hours to 24 hours. The machine is configured never to sleep, so only the hard disk and screen is set to sleep after a period of time. And it's when these are sleeping and you come to use the machine after a number of hours that when you move the mouse you notice the system clock has froze and the beachball/spinning pin wheel is happening aka its froze.

So I guess the big test is yet to come, hopefully tomorrow morning when we wake up and my wife goes to use the machine it doesn't have the same old fault thats happened.

As you can see I've done quite alot of troubleshooting and this problem has process has taken me about a good 2.5 weeks.

And thankfully having a supplier who stands behind and backs the product they sell certainly helps. As always they have been extremely good about the whole thing and that in turn makes things alot easier knowing that you dont have to battle with them.

I can without a doubt recommend epowermac for your next purchase, as they have stood behind what they sold (as per the website stating that the memory is fully guaranteed).

Of course things aren't over yet, however I thought I should post and share the experience.

Guess we'll know what happens next within the next few days or so when something does or doesn't happen in regards to the current configuration.

I kind of got lost when you talk about the second replacement chip you received.


What brand ram is it? Corsair ram is causing all sorts of nightmares on macbook pros, which is clearly documented in corsair's own forums.

Also Apple hardware test is crap, as most mac tech sites will tell you. Use Memtest, running in safe mode:

http://guides.macrumors.com/Testing_RAM

<strike>I read on one of the mac weblogs the same symptoms that you were having (able to move the mouse but all apps frozen) the author then installed the latest intel firmware which seemed to have fixed the problem</strike>
okey i've got my wires crossed, I've found the weblog post that had the same symptoms as you described, unfortunately for him his hard drive crashed sorry.

Here's the link to the post.

<div class='quotetop'>QUOTE(choy @ Jun 23 2006, 01:37 AM) [snapback]187512[/snapback]</div>Brand is not Corsair. Its a brand that is imported by a distributor. It's sold and backed by epowermac. Hence I used them as I know they wont burn me if the chip has problems.

Basically as a sum up of things... I've had 3 chips in total (2 of which from the same distributor chain). It's only now that I have the 3rd chip from different distributor that it seems to work on its own (just not with factory 512mb in machine as well). Guess the whole running matched pairs is very true.

Following cominbations

dimm0: 512
dimm1: 1gb

dimm0: 1gb
dimm1: 512

dimm0: 1gb
dimm1: none

dimm0: none
dimm1: 1gb

Alll the above combinatons would freeze when using the first 2 chips I was sent. Of course the system ran fine when the factory 512mb was the only chip. Hence it appeared to follow the new memory.

Currently, the 3rd chip has only frooze in the following config;

dimm0: 512mb
dimm1: 1gb

And this config could be put down to reports its a mixed size/brand, and as such probably wont work.

As of now I am running (and have been running for the past 1day 1hr)

dimm0: 1gb
dimm1: none

And it is yet to freeze. Normally the previous 2 chips in this configuration would have already frooze the system.

Hopefully things will finally just continue to work, and I guess if I can run the factory chip with it due to it being not matched, then no big deal. It was a bonus if it worked, and if it didn't I was going to sell the factory chip and my factory chip from my mac mini anyways.

Yes, Apple Hardware Test on the intel machines is crap. It dont even support a loop mode. How stupid...

memtest showed no errors on all chips previously too, as I ran that too.

thanks for the feedback. Much easier to understand oyu rmemory combinations the second time!

Sound like it was the matching that was the problem. Good luck - hopefully your last combination will keep working.

Just curious, what speed memory are you using?

All the new Macs require 667mhz and I'm assuming that's what you bought, however ddr2 so-dimms come in other speeds as well...the most common is 533mhz....and your supplier may have given you those instead.

If you got 533 ram and put it in a macbook it may be trying to push it to 667...some ram might take it but it all depends on yeild quality and if the ram is 667 underclocked to 533. The most common problems assiociated with overclocked ram is your computer starts freezing.

The other thing to check is that the ram hasn't been clocked up to 667 and sold as such (common and dodgy practice for the cheap suppliers)

Bartron

Of course its ddr2 667Mhz, as per the epowermac website (which they back us being totally supported etc).

The point of my post is to try and educate others on the possible issues caused, yet the chips always tested fine. Yet they couldn't even run without any other chip in the machine. They still locked up and froze the machine.

Although touch wood 3rd chip on now works on its own, just not with the factory hynix 512mb in the machine also. Although I did only try it in one order, so when time permits I will put it in again in a different order just to see. Worse case I sell the Apple 512mb chip from the macbook pro and sell one of the 256mb chips from my duo mac mini, both I dont really need anyways.

Of course the biggest point I was probably making is if you buy 3rd party memory of any type much sure the supplier is going to back it so when you do have issues they dont push back on you. John from epowermac as always was a pleasure to deal with. Even when things didn't goto plan. Good on them too, as they have always been very good service/support wise.

<div class='quotetop'>QUOTE(purana @ Jun 24 2006, 05:45 PM) [snapback]188006[/snapback]</div>That's cool.....just that I've seen some ddr2 memory marked at 667 when it was really 533...mainly the cheap stuff. Most people wouldn't notice as a lot of laptops are (were) still running 533 memory anyway....things are a changin though and good to know there is a supplier out there that will back you up.

.... and as one final test... ran the machine with 512mb factory chip + 256mb factory chip (as pulled from my mini duo).

Bingo same problem. So its not the memory, its the stupid machine...

Updated my long running apple case, and then had my wife call in and let Apple have it. Got that case pushed up and advised it would be reviewed when a tech looks at it and makes recommendations.

Thought it was going to take a few weeks, but managed to arrange something through the company I bought the machine with, turns out the service manager is very helpfull and knows some of the people I use to deal with when I was a certified tech and calling TAC every so often.

Dropped machine off so that a tech could see and then make recommendations to Apple (with a case update to my case) so Apple can review after that (will they replace or not). Currently pushing to have it replaced under DOA, as the fault occured within the DOA period, but I followed the route any normal person would with regards to memory, as it did seem like that as the fault. But 3 weeks on and thats totally not the case (as it faults with Apple memory).

The machine works fine on 512mb, anything more it just freezes or reboots as per the above posts. Could be a combination of things, and I wouldn't rule out airport wireless as being part of the problem, but who knows.

At 3.1K for the machine, just want something that works correctly as it should.

About to go pickup the machine, as we are going to continue to use it, until a decision comes back. As the machine got reviewed overnight and today. (Very happy with the service, they did me a favour and I owe them. Although I did do 3 weeks of troubleshooting, in great detail).

Will confirm the recommendation from tech in about 40mins, when I go pick it up.

Unit was reviewed... and service tech agrees with my findings... further more they found that the machine under heavy load would have video issues (very serious ones). Once again further prooving it has more then one problem with the logic board.

Just awaiting decision that it will be DOA replaced.

And then we can finally go onto using that extra memory without it crashing every 12 hours or so.

I would like to hear how things go as my MacBook Pro has been locking up about once a week...