dsc106 Posted May 4, 2007 Share Posted May 4, 2007 SPECS: AMD Athlon x2 4800+ sse3 ASUS A8N-SLI Premium 4gb ocz pc 3200 ddr RAM XFX Nvidia GeForce 7800gt 256mb 200gb IDE Maxtor HDD secondary master, one partition Ok, I kept getting these random freezes, where I'd do something CPU intensive, and then boom, grey screen comes down "you need to reboot" - I couldn't figure out why. Well, I busted out the system monitor and started trying to watch what happen. My 2 cores are only being used at 15%-30% when do tasks, such as decompressing an archive or something... However, the RAM usage starts climbing and climbing and climbing as the system tries to take full advantage of my 4GB of RAM. Well, I remember that in WINDOWS, even though I have 4gb, the OS can only use about 3gb. The reason is because under 32-bit, there is only 4gb total to be addressed. And the system uses that other 1gb to write addresses for my other devices, such as my soundcard, LAN, PCI devices, and my 256mb graphics card. This leaves about 3gb to be used. Well anyway, when I'm doing something intensive, the RAM usage keeps climbing... until it hits about 3gb and which point IMMEDIATELY... and EVERY TIME... right then the comp goes to gray screen and freezes, telling me I must reboot. And so therefore, I am pretty sure that problem is related... But how do I solve this problem? How do I stop OS X from trying to use all 4gb, then running out of memory at 3gb and getting all messed up (if that is what is happening, or something like that). I think I know what is wrong, I just have no idea what to do about it... Please help! Thanks! Link to comment Share on other sites More sharing options...
hecker Posted May 4, 2007 Share Posted May 4, 2007 I think it could have something to do with the RAM modules not working in-sync with eachother. Are the modules identical or even dual? If they're not, you could try lowering their timing settings (BIOS) a bit and testing until the system works stabile. hecker Link to comment Share on other sites More sharing options...
dsc106 Posted May 4, 2007 Author Share Posted May 4, 2007 Well, they are all 4 the exact same models (like exact same). I pulled one out and now I can't get the system to freeze no matter what I throw at it. So... I could just leave the stick out. However, I would be interested to know if there is a way to set the OS to boot without using one of the slots/device IDs or something? I'd rather just leave the stick in... Link to comment Share on other sites More sharing options...
sg Posted May 4, 2007 Share Posted May 4, 2007 i doubt ram usage is the case, since OSX will cache as much as it can in your RAM from the start, there really isnt any unsued ram. Link to comment Share on other sites More sharing options...
dsc106 Posted May 4, 2007 Author Share Posted May 4, 2007 i doubt ram usage is the case, since OSX will cache as much as it can in your RAM from the start, there really isnt any unsued ram. Make sure to read all of my post. It's absolutely, without doubt, a RAM issue, and I've fixed it by removing a stick. I'm looking for a way to disable that stick or cap osX's recognition at 3gb. Read the post for why that is an issue. Link to comment Share on other sites More sharing options...
shoarthing Posted May 4, 2007 Share Posted May 4, 2007 1) OSX (well, the version you're talking about) doesn't & cannot see/use more than the usual 2.8 - 3.2-ish GB available to 32-bit OS' depending on any addin ROMs eating away at the address space - doesn't matter how much memory you have installed, that's all the OS can get at. 2) If you don't believe this, fire up 'Activity Monitor' in the Utilities folder, click 'System Memory' - it'll show you some random amount of installed memory around or less than 3.2GB 3) You can check in your motherboard's BIOS that you do not have 'memory remapping' enabled [sticks the 'lost' memory above 4GB address-space & gets at it through PAE, requires ACPI 2 & a suitable server-class 32bit or any 64bit OS] - tho' this should not in fact affect things, even with a very buggy BIOS. 4) why not just pull a stick out if this works for you? . . tho' 3) above [having memory remapping enabled] can screw OSX as described. Link to comment Share on other sites More sharing options...
joneSi Posted May 4, 2007 Share Posted May 4, 2007 Well, I can understand wanting to have all four installed because you have them. But IDK how the performance will be with just 2 gigs compared to three. IIRC there must be pairs for the dual channel to work. Would macbench be able to tell which setup is better? Also, there are plenty of people with 'real' macs that have more than 4gb of ram. And these seem to be able to function without a problem on OS X. The new Mac Pro will take what, 16gb of ram? What does the system do with the ram if it doesn't see anything above 3.2gb? I know these aren't the same machines, but I would think that similar memory addressing would work even though he's on an AMD setup. IDK, I just thought I would offer something here. GL joneSi Link to comment Share on other sites More sharing options...
hecker Posted May 4, 2007 Share Posted May 4, 2007 Interesting posts guys. You got me really intrigued now hecker Link to comment Share on other sites More sharing options...
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