dying4004 Posted March 30, 2008 Share Posted March 30, 2008 Guyz i have been using OSX 10.5.2 for last 2 months with Gigabyte GA_945gcmx s2 and C2D E4500 2.2 GHz. I have been overclocking it for last 1 month. Yesterday I increased the overclock to 2.7 Ghz and found that booting into MAC 10.5.2 doesnt find any SATA drives. Reducing the overclock to 2.4 Ghz find SATA. do u guyz know actually how to overcome this??? cheerz Link to comment Share on other sites More sharing options...
MacUser2525 Posted March 30, 2008 Share Posted March 30, 2008 Guyz i have been using OSX 10.5.2 for last 2 months with Gigabyte GA_945gcmx s2 and C2D E4500 2.2 GHz. I have been overclocking it for last 1 month. Yesterday I increased the overclock to 2.7 Ghz and found that booting into MAC 10.5.2 doesnt find any SATA drives. Reducing the overclock to 2.4 Ghz find SATA. do u guyz know actually how to overcome this??? cheerz Most likely the system bus speed getting out of wack a lot of BIOS's have a setting in them to lock the PCI/PCI-E bus to a fixed rate you may want to check if such a setting exists in yours. Link to comment Share on other sites More sharing options...
dying4004 Posted March 30, 2008 Author Share Posted March 30, 2008 a'rite just had a dig at the bios if i make pci-e async so that id doesnt increase with oc machine doesnt boot overclocked at 2.8 ghz leopard 10.5.2 doesnt find SATA win xp and vista finds SATA at overclocked 2.8 ghz Link to comment Share on other sites More sharing options...
MacUser2525 Posted March 30, 2008 Share Posted March 30, 2008 a'rite just had a dig at the bios if i make pci-e async so that id doesnt increase with oc machine doesnt boot overclocked at 2.8 ghz leopard 10.5.2 doesnt find SATA win xp and vista finds SATA at overclocked 2.8 ghz Hmm not really sure what is going on here then usually if one OS is not finding the drive/having problems with the OC then it happens in all of them on the machine. For the setting you changed does it have a fixed 100mhz option? If so then you should try that and perhaps post all the settings you are changing when doing the OC here so we can see what exactly you are changing. Link to comment Share on other sites More sharing options...
dying4004 Posted March 31, 2008 Author Share Posted March 31, 2008 i have only 3 options in pci-e 1. auto 2. sync 3.async async doesnt work . it doesnt even boot Link to comment Share on other sites More sharing options...
MacUser2525 Posted March 31, 2008 Share Posted March 31, 2008 i have only 3 options in pci-e 1. auto 2. sync 3.async async doesnt work . it doesnt even boot That is not impressive then it is fairly limiting to say the least I guess you will have to try each one and see how far it will go and accept that as your limit with that board. Link to comment Share on other sites More sharing options...
tazevedo317 Posted March 31, 2008 Share Posted March 31, 2008 if you really want to make your CPU scream. get an Asus P5K-VM. i have an e4400(similar to yours. just lower speed) and im hitting 3.5. only thing stopping me is os x. you should be getting alot more out of that processor. and the p5k-vm also allows for future hardware changes such as 45nm cpus. 8gbs of ram. etc Link to comment Share on other sites More sharing options...
Chrystopher Posted April 3, 2008 Share Posted April 3, 2008 Got the same problem here.. Link to comment Share on other sites More sharing options...
sarahbau Posted April 7, 2008 Share Posted April 7, 2008 I have a different motherboard, but I have a similar limitation on mine. Once the PCI bus gets past 40MHz, SATA no longer works. I was able to get my CPU to 3.6GHz (240MHz FSB, 40MHz PCI) when booting from SATA, but when I tested it with a PATA drive, I could get it to 3.825 GHz (255MHz FSB, 42.5MHz PCI). Link to comment Share on other sites More sharing options...
Bearcat Posted April 7, 2008 Share Posted April 7, 2008 I had this same problem on a P5KPL-VM Asus motherboard. When I initially overclocked a Q6600 to 3.0ghz, the sata hard drive disappeared. It re-appeared when I put the processor back to stock speeds of 2.4ghz. I eventually found by moving up slowly that the sata drive disappeared when I got to 2.93ghz, but even a little lower it was not stable. Would get errors reading from the DVD drive. When I rechecked the bios, I found in the overclocking screen, the PCI setting was set to auto, so I suspect it would go up and down as I changed the fsb setting. I selected that to see what the settings were, and lo and behold, they were auto, and a number of speeds. I set the PCI speed to 100, and then set the fsb back up to 1333, running the processor at 3.0ghz. This change made everything stable. No more errors reading from the DVD, no sata hard drives disappearing. Been running 10.5.2 for 5 days like this, with no issues. Link to comment Share on other sites More sharing options...
kramer2k Posted April 11, 2008 Share Posted April 11, 2008 I have the same problem on a GA-P31-DS3L...if I go 1 MHz over 399, no boot for me... But I've got my PCI-e bus locked at 100 mhz...and it boots to windows fine with FSB of greater than 400 The AUTO setting for my PCI-e bus locks it at 100MHz (or at least that's what the manual says) Edit: So it turns out that I can get it to boot at 400MHz fsb if I set my PCI-e bus to 117MHz (116 won't boot) Link to comment Share on other sites More sharing options...
goebish Posted April 18, 2008 Share Posted April 18, 2008 Running your PCI-e bus over 100MHz is not recommended. It can hurt your graphic card and other PCI-e peripherals very quickly ! Your problem is really strange. Did you try to increase a bit your NorthBridge voltage ? Is your SATA configured as AHCI ? Link to comment Share on other sites More sharing options...
tomnic Posted May 28, 2008 Share Posted May 28, 2008 My Gigabyte GA-945GCMX-S2 tops at 321 MHz FSB, any frequency over that makes my sata stop getting recognized by Leopard, but it is still fully recognized by BIOS, and can boot any dvd but osx86. The problem arises from the impossibility to fix PCIeX and consequently PCI frequency. Use this formula to calculate the actual PCI frequency: PCI = FSB * 33 / 266, in my case, PCI = 321 * 33 / 266 = 39,82 MHz, still fine, everything over or equal to 40 MHz makes sata crazy. We have to mod the bios to allow us to set FIXED pciex frequency at 110 or 115 MHz, using mobos with such setting made me succeed in overclocking. Where can I find a bios editor? Link to comment Share on other sites More sharing options...
hg2007 Posted May 28, 2008 Share Posted May 28, 2008 Guyz i have been using OSX 10.5.2 for last 2 months with Gigabyte GA_945gcmx s2 and C2D E4500 2.2 GHz. I have been overclocking it for last 1 month. Yesterday I increased the overclock to 2.7 Ghz and found that booting into MAC 10.5.2 doesnt find any SATA drives. Reducing the overclock to 2.4 Ghz find SATA. do u guyz know actually how to overcome this??? cheerz I had a similar problem with the same processor not with my SATA drives but my RAM, 3GB RAM disappears after i overclock over 2.7ghz. 245 fsb it seems to cut out on. Link to comment Share on other sites More sharing options...
Dr. Hurt Posted January 17, 2015 Share Posted January 17, 2015 Sorry for reviving an ancient thread, but I encountered this problem too when I installed an e8400 in a GA-945GCMX-S2. This happens because the BIOS automatically raises the PCIe frequency to 115 MHz to be able to cope with the 333 MHz FSB required by the CPU. IOATAFamily doesn't seem to like that for some reason. Interestingly though, both Windows and Linux are perfectly stable. Workaround: Set FSB to a max of 320 MHz and all will be fine Link to comment Share on other sites More sharing options...
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