Macbook Pro late 2008, and 1333mhz RAM module

Can one or all of you that has successfully switched from DDR3 1067Mhz to the 1333Mhz RAM clarify a couple points for me please? Sorry to ask but I'd like to make sure I'm on the same page before I do it.

a) Were any of you already upgraded to Lion? If not, have any of you done the Lion upgrade yet?

b) Are you still operating your MBP without any related issues?

c) And lastly, were you already on the correct Boot ROM Version? Or???

I somehow missed this, but in case you are still wondering, I am sill running a mixed 1067/1333 setup (1 x 4Gig each) and the system's stability is still rock solid.... Well, as solid as can be expected from a system being pushed to the limit with multiple VMs and a compiler quite frequently running full tilt, anyway... 😀

I've upgraded to Lion and have run the system in both 32bit as well as 64 bit modes without any issues, and my BootROM was on the latest version before I popped in the last 4Gig DIMM, yes.

jaboth, your system is "rock solid"? how do you measure that? If it runs without problems, you are lucky, your situation does not prove anything. The os and apps have nothing to do with it: in your situation you have a mixed set of Ram which means that the modules which do not have the correct spec are being downclocked easier than when you have only incorrect-specced modules. And obviously you have a brand that allows downclocking easier than other brands, you are just lucky.

Again: what is displayed in system information is what it says on the modules, NOT what it running speed is.

Thus your chance that the system is not having issues is a little bit greater. That is all. 32bit 64bit Snow Leopard Lion VM's have nothing to do with it !

As an aside, my system information displays both DIMMs as 1067.

So, while it's possible, if not quite likely, that I'm just lucky, that does not invalidate my experience, nor does it mean that anyone else should be precluded from attempting a similar setup.

As to how I determined the solidity of my setup; why, the same way any amateur or professional scientist would: observation, measurement and logging. While I in no way claim to be a scientist, I gave been involved in the technical field and with technology for long enough to have enough of an understanding of the experimentation process...

In my experience and with my configuration on my system there has been no measurable difference between the stability of my System before and after the upgrade. There has, though, been a marked inprovement in my workflow, mostly due to my work-profile.

And there then is where the use of VMs become relevant. Since I use VMs extensively as development machines I tend to saturate my available RAM with a depressing regularity. Thus I quite frequently use all 8Gb of memory which, should the secondary DIMM have been more prone to failure, should have created more frequent failures, hangs or crashes. That has not been the case in my configuration.

Now while it's true that I have installed a decent brand of memory in my system, it would be what I would advocate to anyone else as a matter of course anyway: always install the best hardware you can get for a reasonable price. Both if those are, of course, subjective measurements and should be decided by whoever is contemplating the upgrade...

I have a 2.53 GHz MBP Late 2008 Boot ROM MBP51.007E.B06 and only installed the 1066 MHz RAM (2 X 4GB). Running Mountain Lion. I played it safe by not going for 1333 MHz in case of downclocking issues. So far, so good.