Hello fellow Mac fans,<br><br> I was searching for various upgrades and add-ons for the PowerMac G4 I plan to buy when I came across SDRAM DIMMs rated at 150 MHz versus the standard PC133.<br><br> It is my understanding that this rating simply indicates how fast the RAM Chip is capable of operating (in warm and fuzzy terms). That specification, combined with the CAS latency and Ms (Millisecond) rating equals the total speed of the RAM chip.<br><br> It is also my understanding that being exactly the same SDRAM DIMM chip, except rated to higher MHz, means you can use PC150 in a PC133 slot.<br><br> With the great expense of a new PowerMac G4 system at hand, I have been looking to make it the best system possible, in order to extend its usable life. I plan to purchase it with Ultra160 SCSI HDs (rated @ 10,000 RPM!), dual processors, GeForce3, etc. Of course, I want the fastest RAM as possible as well. Apple doesn't seem to tell you what type of RAM is in the G4 at default (specifications of the chips) and their ridiculous RAM prices have made me consider after market RAM. Since the RAM in the G4 is a standard SDRAM finding cheap and fast PC133 chips is easy. I had my eyes set on three PC133 512MB CAS latency of 2 and a <7 MS rating.<br><br> Then I found the PC150 RAM. Exactly the same specification (512MB/2CAS/6.5MS) except rated to 150 MHz. So, what I am asking is whether anyone has tried these chips, any ideas on whether or not they will work at all, etc. I also plan to purchase a RAM cooler, to "strap-on" the chips to keep them as cool as possible to avoid heat problems inherent to high speed processing. Technically, they should just plug in and work faster then PC133, but who knows.<br><br> I could, of course, just wait till Apple puts DDR SDRAM in the G4s, but then I would have the same question except with high rated DDR chips :)<br><br> Any info, tips, etc, would be most appreciated.<br><br> Cheers,<br><br> Adrian<br><br>