PowerMac G5 Upgrades, Tweaks, Hacks, and Diagnostics

Discussion in 'PowerPC Macs' started by AmestrisXServe, Mar 5, 2014.

  1. AmestrisXServe, Mar 5, 2014
    Last edited: Mar 5, 2014

    AmestrisXServe macrumors 6502

    Feb 6, 2014
    I'm starting this thread to discuss all of the following, for Powermac G5 systems:

    System Upgrades

    PCI Cards
    PCI-33 Cards: 1.6 and 1.8GHz systems with the 32/64-bit PCI-33 Southbridge
    PCI-X Cards: 2.0Ghz through 2.7Ghz G5s, with the PCI-X Southbridge
    PCIe Cards: Quad-Core G5s with the PCIe Southbridge

    RAM Upgrades
    PC-2700: PCI-33 Systems with the early Northbridge
    PC-3200: PCI-X Systems with the 2004/2005 Northbridge (2.0Ghz)
    PC-3200: PCI-X Systemns with the 2005 Northbridge (2.5/2.7GHz)*
    PC-4200: PCIe Systems with the last Northbridge variant (Liquid Cooled Quad G5s)

    Processor Upgrades
    Changing CPUs from one system to another.
    Attenuating and Calibrating CPUs
    Thermal Enhancements

    HDD Upgrades
    SATA Upgrades & Drives
    SAS Upgrades & Drives
    SSDs and Similar Devices
    Optical Drive Upgrades
    eSATA & NAS

    Service & Repair
    Essential facts on repairing G5s.
    Q&A for G5 Service
    Repair, Diagnostics, and Service Flowcharts
    Service FAQs.

    Video Cards & Displays
    Viedo card upgrades:
    Multi-Display Setup and Options

    Networking & *nix
    Server Use
    LAG Options
    Remote Access
    Shell Scripts
    Command Line Performance Options
    Developer & Server Tools for General Use

    System Optimisation
    G5 Software; especially G5-enabled software.
    Other G5-Specific topics.

    If you have anything to contribute, please do so. I would appreciate if someone could sticky this topic, to make it prominent for people to view, and to contribute to it.

    I think a good, initial point of interest is overclocking, CPU changing, and the related thermal calibration, and thermal dispersion methods. Does anyone have something to contribute along these lines?

    I will work on some points of interest, and post them. Please note that I request that double-posting in this thread be allowed, purely to allow multiple topics to be contained in single posts, so that if a person wishes to post regarding PCI cards and about networking, that they may post two replies, each covering one subject, for thread, and quoting cleanliness, to improve readability.
  2. Intell macrumors P6


    Jan 24, 2010
    You may want to avoid the topic of overclocking a G5. It brings of sour memories for veterans of the PowerPC subforum relating to a certain ex-member.
  3. AmestrisXServe thread starter macrumors 6502

    Feb 6, 2014
    Sorry mate, but I won't avoid discussing a potentially interesting, and important topic, because someone I know nothing about caused you trouble at some point. I would never do that, for any reason.

    This is a topic that interests me, and I would like to know about the experiences of others, good, or bad; as would likely other people that own G5 systems.

    If you want to clarify what your problem is, or was, that would be far more useful than asking me to suppress a very viable discussion on an interesting subject matter, especially if it was a technical matter. If it was purely a personal matter, then it doesn't even belong in this (or any other) thread.

    I have never, personally, overclocked a G5 system, so I am naturally interested in what others have been able to do, and what has failed, and I am not going to make any sacrifice because you didn't like someone. Every forum has people that cause mischief, and if we all abandoned any topic that someone of that nature has ever discussed, then there is no point to free expression, debate, or discussion.

    To be perfectly frank, I think that was a very selfish request.

    This topic should be constrained to factual datum, and ideas that may prove valuable; not gossip.
  4. Intell macrumors P6


    Jan 24, 2010
    You're being a bit presumptions in thinking I was being selfish in my previous post. A selfish request would have been be thinking for myself. I was thinking about others within this subforum. As you want to discuss overclocking G5's, look at rabidz7's past posts. You'll find plenty of discussion on the topic there. In summation, it cannot be done to an Apple G5 system.
  5. jrsx macrumors 65816


    Nov 2, 2013
    Tacoma, Washington
    I too am interested to see what others have done with G5s, and if personal matters are going to kill this thread, I would be put out... X(

    Ahem: http://forums.macnn.com/65/mac-desktops/314000/ive-overclocked-my-g5/
  6. AmestrisXServe thread starter macrumors 6502

    Feb 6, 2014
    In the end, it doesn't matter if it can, or cannot work; however, if it is entirely impossible to overclock a G5, that is the correct thing to state here, alongside the specific technical reasons for which it is impossible, and all limiting factors.

    If it is possible at all, that should be worth discussing, and worth documenting, along with any limitations, caveats, and risks.

    Reading every other thread, or pointing to them, en lieu of technical explanations is silly. You should point to a thread as a reference, after giving definitive information. That's rather the point of a FAQ-and Fact type thread.

    I will be adding factual information on each topic, and useful information, such as compatible PCI cards, useful software (with pointers), and such, to the head of this topic, as it accrues, to make it easy to look at the head, find what you want, and click on it to view relevant posts in the thread.
  7. Intell macrumors P6


    Jan 24, 2010
  8. gavinstubbs09 macrumors 65816


    Feb 17, 2013
    NorCal boonies ~~~by Reno sorta
    I'd like to get a DP2.5 from a 2004 model and stick it in my DP2.0 (2005). May happen, but I am watching a nice 2.5 with a 17" ACD at $120 buy it now. Bit tempting :)

    Anywho, my G5 has the Radeon 9650 256MB and the card was given to me; so no clue on price. I honestly can't tell a difference between the 9600 128MB. I also have a SSD in mine which makes it decently fast, but 2x drives in RAID0 could get faster performance than this crapola Kingston SSD (reason why the SSD now lives in the G5 and my Mac Pro has RAID0).
  9. jrsx macrumors 65816


    Nov 2, 2013
    Tacoma, Washington
    This I doubt: It's entirely possible to overclock, but it does require an extremely small soldering iron to do the job. By small, I mean VERY small, and you could easily destroy your computer, which is why you don't see a lot of people on the web doing it. I've read this on some websites.
    I do understand that G5s are nearly impossible to overclock, wheras G4s are much more simple.
    As some say, don't cook the chicken to the point where it's burnt. ;)
  10. Cox Orange, Mar 5, 2014
    Last edited: Mar 5, 2014

    Cox Orange macrumors 68000

    Jan 1, 2010
    I heard swapping G5 CPUs even with the service diagnostics DVD to recalibrate does not work very well. Is that true?

    On the RAM:
    I was adviced by Japamac in another Forum:
    I have PC2-8500 and PC2-6400 RAM in my G5 2,3GHz DC and they are set to PC2-3200 by the OS (at least it is what is reported). Remember that PC2-4200 533MHz is the actual supported speed here.
    I guess, every RAM at or one above PC2-4200 will be set to PC2-4200, all higher RAM gets down to PC2-3200. (Note: yes, both exist. PC-3200 DDR and PC2-3200 DDR2 RAM.)


    On the PCI-card stuff.

    There is a member flyproductions over at cubeuser.de (he is here, too). Maybe you can find him and ask him to share his knowledge (he is very kind, but also has lots of work to do). He has done extensive testing with all sorts of PCI/PCIe cards and even SATA-III in G5s.
    Maybe you can search google for SATA-showdown site:cubeuser.de and for SATA PCI G5 site:cubeuser.de and use google translator. The information should come through, even with the broken english of google translator.

    You are free to employ my list of cards and other posts I answered you in other threads, though.

    From my own experience with my G4. Using a PCI33MHz (32bit card) is pointless. PCI-X / 64bit is the only thing that makes sense, if it goes for speed and not just expanding available numbers of HDDs.
  11. AmestrisXServe thread starter macrumors 6502

    Feb 6, 2014
    From what little information I have, it seems that it is because of how the bus clock and CPU clock are synchronised.

    All that I have seen elsewhere amounts to vague theories, and speculation; but no hard facts. I fully understand the problem however, with matching frontside bus ratios. I would expect two things that have held back any possible progress on this topic:

    1. Lack of practical engineering experience; alongside SMD component skill.
    2. Lack of interest, particularly given that you would need to build an expensive cooling system.

    Overclocking is not, however, a topic specific the CPUs. I reference overclocking in general, including the GPUs on included video cards, or other video cards used on G5s, and so forth.

    I have absolutely naught for physical documentation on overclocking the CPUs, however, this is something you can lump together with CPU upgrades (i.e. changing the modules).

    A list, comprising known working upgrades, is what is valuable for this thread. The more I have to use, the more I can compose a full G5 Upgrades & Technical Information FAQ, which I think would be nice, considering that the G5s are now inexpensive, and easy to find.

    From what I can gather from these other articles, the G5 has a fully-shared clock, which makes alterations to the CPU timing very difficult. You would need to probe the entirety of the main system logic, before being confident in the ability to overclock a system.

    That brings me back to the two breaking points: Those that can do this, likely haven;t the time, nor the interest; and the cost is too high for the marginal gain. That doe not mean it isn't possible, it just means that it is unreasonable.

    The only advantage would be for running PPC-specific software, using the fastest G5s (dual 2.7GHz, and quad 2.5GHz), to boost their performance by a margin of not less than 20%, which would be a rather notable increase on those models. A 200MHz improvement to 1.8GHz system is not worthwhile, given how affordable a 2GHz system is at present.

    The primary logic behind investigating this, in my eyes, is to produce a system faster than anything that Apple had made. A dual, or quad 3.0Ghz system, would be nice, and would be about the most I would expect to see out of a G5.

    That said, either the CPU clock must still be either partially independent of the bus clock, or the clock multipliers must be other than 1GHz, as specified elsewhere. I'll try to collate what I can collect from other sources, and to make something intelligible out of it, when I can spare the time, as it seems to be an adventure merely to collect positive datum.

    I can certainly see why you didn't like this rabidz7 chap: Reading his posts is the literary equivalent to walking into a room, and stubbing your toe on every piece of furniture. I can;t honestly tell if anything on the website in his links was useful, as the Wayback captures don;t include the images; nor do I know if the large block of resistors is either accurate, or useful.

    This is rather why I am asking: While I don;t expect a simple process, if there is a reliable way to overclock (the CPU) on a Dual-2.7Hz system, I have a spare that has other problems (a sensor fault), that I could address simultaneously with an overclocking attempt. The worst case for me is that a machine that is not working right at present, would never again work properly.

    I thus have the luxury to experiment on it. I wouldn't bother without more facts, and even the speculation is so widely dispersed, that it is difficult, if not tedious, to determine what is, and what is not true, or valid.

    I expect you mean for performance reasons, using SATA drives. PCI-33 has other uses, and the PCI-33 on the G5 is 32-or-64-bit, so you can actually use a 64-bit 33MHz PCI card, with a data throughput of 266MB/s, for a variety of applications, including SATA-II, UW SCSI-III, FW800, etc.. THis, assuming that you can locate a 64-Bit PCI-33 card, that is compatible with OSX; hence the need for a list of such products, and drivers for them.
  12. Intell macrumors P6


    Jan 24, 2010
    It's mostly true. G5's logicboard are locked to a certian bus speed. Swapping in a different CPU speed, sometimes even one from a different model, will put the board into a safe mode and the CPU will run at about 900Mhz. There is one or two logicboards that are not locked and do allow different speeds. I think they're the 2.0Ghz and 2.3Ghz from early 2005.
  13. Cox Orange macrumors 68000

    Jan 1, 2010
    Didn't Apple allready overclock the IBM G5 2,3GHz to 2,5GHz? Or was it the 2,5GHz to 2,7GHz or both? I mean there is a reason they did only do 0,2GHz and put liquid cooling to it. Right? (The actual reason for a 0,2GHz speed bump was advertising, since a Dual/Quad 2,5GHz sounds better ;))
  14. AppleFanaddict macrumors newbie

    Mar 4, 2014
    Hey guys i just bought an april 2005 powermac g5 dual 2.0 ghz model. i have already asked a question about upgrading the ram. and i have ordered the ram. so far it will either have 4 gb or 6gb depending on the amount of available slots as some people have conflicting opinions on how many it has. it is currently being shipped so i can't look at it to see how many it actually does have. my question to you guys is, whats the next thing to upgrade? i don't wanna spend a lot of money on it because i already have my macbook pro i do almost everything on. i bought the powermac just as a machine to surf the web and as a desktop as opposed to my macbook. i don't expect it to outperform my i5 pro but i do want to play some older games like halo, and the older call of duty. what should i upgrade next? lets keep it cheap
  15. Intell macrumors P6


    Jan 24, 2010
    Your machine can hold a total of 4GB of ram. If gaming is what you're planning on doing, the next thing to upgrade would be the video card. The best for AGP PowerMacs is the ATI X800/X850. Mac editions of this card are expensive at about $80-$120. You can get a PC one and flash it. The best PC one for flashing is the ATI FireGL X3. You'll need to get a molex splitter to power the card as well. Don't get the PC ATI X800/X850. Once flashed they only do VGA out, no DVI.

    Other well perfoing cards include the Nvidia GeForce 6800 Ultra and the ATI 9800XT, both in Mac edition. The ATI 9600/9650 and Nvidia GeForce 6800 GT are mid range cards and will be decent, but not the best. If you have the lowly Nvidia GeForce 5200, you will very much want to upgrade as it is not very good for Halo or other older Mac games.
  16. Cox Orange macrumors 68000

    Jan 1, 2010
    There are 4 different versions with 2x 2GHz. One model of these has max. of 4GB, two have 8GB and the last has a max. of 16GB allowed.
    If you are sure about the model, that it is an April2005 model (also called early2005), then it is the 4GB version.
  17. gavinstubbs09 macrumors 65816


    Feb 17, 2013
    NorCal boonies ~~~by Reno sorta
    The early 2005 DP2.0 has 4 slots. The 2.3 I believe has all 8 slots available.
  18. AppleFanaddict macrumors newbie

    Mar 4, 2014
  19. Cox Orange macrumors 68000

    Jan 1, 2010
    Oh, you are a lucky boy!

    from the serial in that ad, I found out, you got a CTO version. It has an original real Mac Edition 9800XT graphics card.

    And you are good, it has the possibility to put in 8GB of RAM.

    for more Details, go to everymac.com -> PowerMac G5 -> June2004 Model.

    The attachment shows. What is in the serial.

    Attached Files:

  20. AppleFanaddict macrumors newbie

    Mar 4, 2014
    wow didn't realize i had gotten such a gem! and only for 100 bucks. he had 5 available and they were from a corporate environment and it comes with the original keyboard and mouse so lets hope the one i get comes with that specific serial or similar
  21. Intell macrumors P6


    Jan 24, 2010
    The June 2004 2.0Ghz models are some of the most reliable PowerMac G5 models. As per upgrading the video card, seeing that it comes with the 9800 I'd suggest giving that one a try. It's a mighty good card.
  22. AppleFanaddict macrumors newbie

    Mar 4, 2014
    does anyone know what kind of hard drive i can use to upgrade mine with? all my details have been given above
  23. Intell macrumors P6


    Jan 24, 2010
    You can use nearly any SATA hard drive or SSD, but some limits do apply. If you want to be able to boot from it, it must be 2TB or smaller. G5's tend to not work well or at all with SATA III drives. SATA II drives generally work, but sometimes give problems unless set in SATA I mode. If you get a SSD, remember that the G5 only has SATA I and any extra speed from a SATA II or III SSD would be wasted in a G5.
  24. AmestrisXServe, Mar 7, 2014
    Last edited: Mar 7, 2014

    AmestrisXServe thread starter macrumors 6502

    Feb 6, 2014
    For some reason, Apple decided to restrict the lower-end G5 systems, for each time period, to four sockets. It seems that only the Quad-G5 can use 2GB DIMMs (PC-4200), so if you've a 4-socket model, your cap is 4GB.

    FAQ Entry: RAM

    FAQ Segment v1.1; dated 7th march, 2014.

    Q. What is the maximum RAM capacity of my G5?

    A. This depends on model. In general terms, you can use up to 1GB DIMMs in each DIMM socket. Thus, if you've 4-sockets, you have a maximum of 4GB, and if you've 8-sockets, your maximum is 8GB of RAM.

    The last G5 models, with a 'Quad-Core' use PC-4200 DIMMs, and can accept up to to 2GB DIMMs, and thus have a maximum of 16GB of RAM.

    Here is the list of G5 systems, with corresponding RAM capacities, and DIMM types:
    [U]Year(s) 2002/3 & Early 2004 G5[/U]
    1.6 GHz        4GB      PC-2700
    1.8 GHz        8GB      PC-3200
    Dual 1.8 GHz   8GB      PC-3200
    Dual 2.0 GHz   8GB      PC-3200
    [U]Year-2004 G5[/U]
    Dual 1.8GHz    4GB      PC-3200
    Dual 2.0GHz    8GB      PC-3200
    Dual 2.5GHz    8GB      PC-3200
    [U]Year-2005 G5[/U]
    Dual 2.0GHz    4GB      PC-3200
    Dual 2.3GHz    8GB      PC-3200
    Dual 2.7GHz*   8GB      PC-3200
    [U]Late-2005 G5[/U]
    Dual-Core 2.0GHz    16GB     PC2-4200
    Dual-Core 2.3GHz    16GB     PC2-4200
    Quad-Core 2.5GHz^   16GB     PC2-4200
    *Fastest single-core, dual-G5.
    ^Last, and fastest overall G5 system.
    All 2.5Ghz and 2.7Ghz Powermac G5 systems are liquid-cooled; other models are air-cooled. If you own a liquid-cooled system, check it routinely for any leakage, and immediately repaid this problem.
    [U]XServe G5[/U]
    Single 2.0GHz (ML/9216A*)    8GB     PC-3200 (Must be EEC)
    Single 2.0GHz (M9743LL/A*)  16GB     PC-3200 (Must be EEC)
    Dual 2.0GHz   (ML/9217A)     8GB     PC-3200 (Must be EEC)
    Dual 2.0GHz   (ML/9215A)     8GB     PC-3200 (Must be EEC)
    Dual 2.3GHz   (M9745LL/A)   16GB     PC-3200 (Must be EEC)
    Dual 2.3GHz   (M9742LL/A)   16GB     PC-3200 (Must be EEC)

    All XServe G5 systems require EEC DIMMs. Do not use Non-EEC RAM in these systems!

    To determine if your XServe G5 can use 2GB DIMMs, inspect the mainboard for a marking, near the RAM sockets: 'DDR2-2GB'. A system with this marking can use DDR2 2GB DIMMs.

    Note: The 2GB RAM modules for the supported XServe are PC-3200, (a.k.a. PC1-3200; not PC2-3200). You want DDR PC3200 400MHz ECC 2GB DIMMs: They are usually high-density, and must be EEC. Few vendors sold these, and it is difficult to locate them today. MacOS X 10.3.7, or later, is required to utilise these 2GB DDR modules.

    Q. Do I need to install RAM DIMMs in pairs?

    A. Yes, you should use pairs of the same size DIMMs; using the same manufacturer, and part number, per pair (or overall) may improve performance.

    On four-socket systems, the slots are numbered (1)(2)(2)(1). This is the numbering sequence for installing RAM Pairs. Install RAM into (1), and (1); then (2), and (2).

    On eight-socket systems, the slots are numbered (1)(2)(3)(4)(1)(2)(3)(4).
    Install in this sequence, using the (1), and (1) upper, and lower sockets for your first pair, then the (2) sockets for your second pair, the (3) sockets for your third pair, and the (4) sockets for your final pair.

    Q. Do I need to install EEC, or Non-EEC DIMMS?

    A. A G5 can use either, but you should use one type for all of your memory, for the best results; and if using both EEC and Non-EEC DIMMs, each pair must be of the same type.

    Q. Do I need 'special' RAM.

    A. In theory, no. What you need is memory that is 'low density', meaning it uses only eight (no-0EEC) or nine (EEC) memory packages (i.e. chips), using only one side of the RAM DIMM for the actual memory packages. Some memory will not work in G5s, for whatever reason, so you should buy RAM that you can return, if it does not work.

    Q. I install RAM, and now my system won't start. What's wrong?

    A. Look at the small, white lamp, located by the main power button, and when you press it, note the number of flashes. Three flashes indicates bad, or incorrect RAM. If you are trying to use PC-2100 RAM, the system will also produce three audible alert tones.

    Q. The system starts, but does not see my memory. Why?

    A. You may be mixing compatible, and non-compatible memory types. The system will ignore RAM modules that it cannot use. You may also wish to verify that your memory is properly seated; and finally, that all the solder joints on your DIMM sockets are making proper contact. A broken solder joint will make a DIMM socket unusable, or erratic.

    Q. What is the minimum RAM configuration for a G5?

    A. Two 128MB DIMMs, giving a minimum total of 256MB.
  25. Cox Orange, Mar 7, 2014
    Last edited: Mar 7, 2014

    Cox Orange macrumors 68000

    Jan 1, 2010
    The sentence above about the Quad, being the only 16GB capable one is conflicting, with your list.

    Also there are mistakes. I gave you a hint in the other thread about the "Mac Mini for web coding", and I gave you everymac.com as a source. This site is really reliable! Just check it out, it has all the info.

    See my corrections above in red.

    Not meaning this rude. It is nice you do the work and try to provide a nice accessable list.

    Maybe you find some additional info here:
    http://guides.macrumors.com/Power_Mac_G5 (There is the max RAM for all G5s every produced grouped in model-years, too)
    For the Dual-Core http://guides.macrumors.com/Power_Mac_G5_Dual_Core_(2005)

    Also, if I am allowed to be nit picking the correct nomenclature is PC2-4200, so one sees that it is DDR2. (Even, if you know, that there is no DDR1 PC4200. But there is a PC-3200 and PC2-3200, really! These are not interchangeable.

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