Digital Audio and PC100 RAM

[senrew]

I've googled, but I keep seeing conflicting answers. Some say they can boot a DA with PC100, but the system just won't recognize it. Others say only PC133 will even let it boot.

I've got way more PC100 than PC133, so I was wondering if anyone can give a definitive answer on whether or not a DA can use either memory speed or if it's just PC133?

 

[SlateBlue]

The system bus speed is 133 MHz, so while you might be able to boot the machine with PC100 RAM, you're essentially crippling the machine.

 

[Gorgonops]

Chances are pretty good that it won't work, for one of two reasons:

#1: SDRAM DIMMs have a little EEPROM on them accessed via I2C that stores "SPD" data about the timing requirements of the RAM on the DIMM. Apple's PowerPC machines were pickier than most PCs about RAM and they will generally refuse to enable DIMMs that don't pass a pretty rigorous sniff test, and if the SPD data indicates the module only supports a set of parameters incompatible with PC133 timing the DA firmware will probably fail it.

#2: If the Mac *doesn't* disqualify it and runs it faster than the chips can handle then it will be unreliable. You might not notice right away, it'll often manifest as random network or hard disk transfer errors.

 

[rsolberg]

My guess is that Gorgonops' scenario 1 will be the case, unless the RAM in question has SPD timings for 133MHz but isn't labeled as such. (pretty unlikely). If the RAM is rejected, you'll hear a series of beeps instead of the chime when you try to turn it on. Nothing will appear on the display and it will not boot. If you take the offending RAM out and put the machine back to the original configuration, there's a chance it will beep instead of booting even with the original RAM. If this happens, you'll need to clear the error by resetting the SMC. (different from resetting the PRAM)

 

[CC_333]

...you'll need to clear the error by resetting the SMC. (different from resetting the PRAM)

Just so there's no confusion, this is referred to as the PMU On PowerPC Macs, not SMC (the SMC is an Intel thing).

c

 

[niner]

I did some googling as well as searching on eBay.  1.5 GB of PC133 should cost you $18 plus shipping.  I Don't know what your situation is monetarily but I'd rather pay the $18 than chase random memory errors.  Macs do tend to be pickier on RAM than PCs do and what you can get away with on a PC won't usually fly with a PowerPC Mac.

 

[senrew]

Oh, yeah, RAM is dirt cheap right now. Just trying to maximize what I have before hitting up ebay or whatnot.

Found a 128 stick of PC133 and dropped that in. Swapped the CD for a CDRW/DVD Combo drive, added a second hard drive, and installed Tiger on the second drive.

For only having 256MB total, and a 466mhz G4, Tiger is pretty OK as long as I don't do more than one or two things at a time and keep my expectations realistic.

The last current mac I had was the last 12" G4 ibook with Tiger on it. Bone stock I remember Tiger being laggy as all hell. This DA is...not too horrible. I'm even able to zip around mactintosh garden with the built in version of safari without issue!