G4 Dual 867Mhz PowerPC - Optimum ram specs - Advice needed

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After 6 great years of service from my blue & white G3 40 Mhz PowerPC which I only ever ran OS 9, I have just bought myself a Dual 867 Mhz PowerPC G4 with 1 MB L3 cache per processor. Unfortunately it came with a single slot of ram only, being a 256MB, DDR 266MHz, CL 2.5.
Does this sound like it could be the original ram that it shipped with? The only brand i.d on the ram is a logo on the sticker which has a capital M with a oval ellipitical ring drawn through it.
Anyway i want to maximize the G4's ram up to 2GB using 4 x 512MB slots of ram.
Being two excited and not willing to wait, yesterday I went and bought 2 x 512MB DDR400 items made by Veritech not knowing if the ram was any good or even compatible. I have put both in the G4, but I dont know if its running good or bad since i just started using it and OSX as well. Anyone heard of the Veritech brand before?
It was cheap, but i was hoping someone could tell me if it is was nasty as well.
Is DDR400 ram suitable for my G4? I can still return or swap the ram at the store i got it from, so can i please get some advice on whether the ram i bought is suitable or not, and if not, what spec and brand should i buy instead. Someone suggested that my G4 will run better if i only use the 2 new 512MHz items, rather than using the single 256MHz as well. Is this true?
Some advice on how to optimize my G4 in regards to the ram specs and any other tips on getting the most from my new mac would be greatly appreciated.
BTW, i have installed 10.3.8

Thanks Dan
:confused:
 
If your G4 starts with no error tones, and is running OK, and recognizes all the memory (check in your System Profiler) then the memory is OK to use.
It's still possible that the memory is not fully compatible, which means you could blame the memory if you now begin to have unusual error messages, new lockups, unexpected quits on applications. You could just watch for major problems you have not had before installing the upgrade.

There's a lot of memory suppliers, some are better than others. I have got the cheapest brand before with no problems, but others who post here sometimes report nasty issues when going 'on the cheap'. My recommendation is to only purchase from a place that will allow an easy return if the memory doesn't work properly.
 
The machine you have is a Mirrored Drive Door (model name).
Original memory specs; PC2100, unbuffered, 8-byte, nonparity, DDR SDRAM

I think G5's are the only Macs that use DDR400.

Check About this Mac under tha Apple and see if the memory shows up.

Someone suggested that my G4 will run better if i only use the 2 new 512MHz items, rather than using the single 256MHz as well.
Click to expand...

Not true, use it all.
 
All the ram shows up using the "about this mac" function, all 1.25GB of it.
But even though it shows does it means it runs sweet?
The reason i question the ram is that my old 400MHz G3 with 768MHz of ram running os 9 seemed a whole lot smoother than the G4 with dual processors and 1.25GB of ram. Altough i am totally new to osx i thought it would be a lot smoother than my old G3. I could open photoshop, itunes, and more all at once, and the G3 would still be quick.
 
The machine boots fine with no error or crashes. It just doesnt feel as fast as i thought it would.
 
OS X is very different from OS 9. what version of OS X are you using?

DDR 400 is compatible with DDR 266. Your RAM should be fine, but if you return it an get DDR 266, you might save a few dollars.
 
DDR400 is dual-channel RAM. I don't think this RAM is compatible with this Mac. You might have to get something like DDR333 single-channel. AFAIK, I don't think there are single-channel DDR modules.


ADDENDUM:
I meant to say on the last sentence that I didn't think there were single-channel DDR400 modules. Sorry for my mistake.
 
nixgeek said:
DDR400 is dual-channel RAM. I don't think this RAM is compatible with this Mac. You might have to get something like DDR333 single-channel. AFAIK, I don't think there are single-channel DDR modules.
Click to expand...
All DDR is dual-channel(sic) (DDR = Double Data Rate), but most Macs that use DDR do not use it fully (only in single mode)
The 'down' performance with DDR is not the memory's fault, it is the memory bus/controller.
The difference when using a DDR system, and only a single rate memory bus for MOST operations should not be that noticeable. I would rather suspect problems with the OS. As has already been said, a clean install of OS X will give your system the best chance when you are trying to pin down problems with performance. Your Mac will use faster memory perfectly well, the system will simply use it at the memory bus speed. Faster memory has no advantage when used in a system with a slower memory bus, except for availability. And, the slower (matching the memory bus) memory will likely be less expensive.
 
DeltaMac said:
All DDR is dual-channel(sic) (DDR = Double Data Rate), but most Macs that use DDR do not use it fully (only in single mode)
The 'down' performance with DDR is not the memory's fault, it is the memory bus/controller.
The difference when using a DDR system, and only a single rate memory bus for MOST operations should not be that noticeable. I would rather suspect problems with the OS. As has already been said, a clean install of OS X will give your system the best chance when you are trying to pin down problems with performance. Your Mac will use faster memory perfectly well, the system will simply use it at the memory bus speed. Faster memory has no advantage when used in a system with a slower memory bus, except for availability. And, the slower (matching the memory bus) memory will likely be less expensive.
Click to expand...


Correct me if I'm wrong, but you seem to be confusing dual-channel and single-channel DDR memory with DDR and SDR busses. There are both single-channel and dual-channel double-data-rate (DDR) memory modules. Single-data-rate (SDR) memory, to put it simply, processes data per cycle on the buss. This is why PC-66/100/133 memory can work on a 66/100/133 MHz bus. It's a clock for clock rate. Sure you can use PC-133 memory on a 66 MHz front side bus, but the PC-133 memory will slow down to 66 MHz speeds.

DDR RAM started its use when the front side bus was dual-pumped, as in the AMD Athlon XP systems. What would happen is that twice the amount of data is processed in only one cycle, hence the dual-pumped moniker. So a 266 MHz front-side bus motherboard would actually have a true clockrate of 133 (133x2=266, 166x2=333...give or take a few decimal places...this is usually rounded off). To be able to match this double transfer rate, the RAM had to process this at the same rate, otherwise there would be a significant bottleneck (This is what happened to the 400 MHz FSB Pentium 4 systems. They were 100 Mhz quad-pumped, processing 4 times the amount of data in one cycle. They only saw performance with Rambus memory, but since they were so expensive, manufacturers brought down costs using PC-100 memory. So now you have 4 times the data per cycle, being processed one at a time by PC-100 memory. Big slowdowns.)

See here:
http://www.pctechguide.com/03memory_DDR_DRAM.htm

What i was referring to with single channel DDR and dual channel DDR was with the memory controller, which you are correct on. Apparently it seems that dual-channel DDR is backwards compatible and will work as a single channel DDR module if it needs to. See here:

http://www.pctechguide.com/03memory_Dual-channel_DDR.htm
 
unixgeek- if you re-read the articles in the links you provided, you will see mentioned that 'there's no such thing as Dual-Channel memory' . Any DDR memory configuration still needs a memory controller that will utilize the memory at a double data rate, and I just pointed out that most Macs that require DDR do not have this capability (until the G5, AFAIK). All memory buses have a minimum speed specification. If the memory bus requires a DDR module spec of PC2700, then PC2100 will not function at all. PC3200 in the same system will be fine, but will perform at the slower speed (PC2700/333 MHz) which is all the memory controller will allow.
A dual-channel memory controller is a different animal, requiring identical pairs of memory modules to be used.
This is enough techno/gee-whiz stuff, and a little off track for this thread.
 
I forgot to mention previously that the ram i purchased is PC2600 according to the system profiler. Specs for my G4 specify PC2100 or PC2700, but apparently it will support PC3200 DDR400 according to www.eshop.macsales.com
My G4 seems to accept the ram ok with no system problems occurring, just thought it should be faster. I did install the OS 10.3.8 fresh, but not with the extra ram inserted, only with the original PC2100 DDR266 256MB ram.
Any further thoughts guys?
 
Adding memory, by itself, will not make your system faster. More memory, in general, will allow the OS X to be more stable, and require fewer writes to the hard drive for memory swap-outs. This should make your system SEEM faster.
But, you still have the same hard drive, processor(s), and the various chips and buses on the logic board. You also still have the same video card. You could be having some minor directory problems on your hard drive. Running a utility that can rebuild/repair your disk directory (such as DiskWarrior) can help with drive performance, or replacing your hard drive with a faster (or just newer) hard drive can allow your system to have faster disk access, and seem to function faster.
The various OS X troubleshooting techniques, such as repairing permissions, removing system cache files, and other means of 'optimizing' the system can make a significant difference in the 'feel' of your system.

Memory is just a good start... Good Luck!
 
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