RAM Upgrade: Toshiba Satellite Pro 4600

I added a second 128MB SODIMM to the empty slot in a friend's 4600 and the 
system did not see it.    I switched the modules over and still only got 
128MB reported for system RAM so I think that the second slot may be dead - 
have I missed something?    I will be taking a look at the machine tomorrow 
and I have discovered that on another (earlier) Toshiba model, you have to 
use Fn + F3 repeatedly to enter Boot mode before powering down and 
installing extra memory - does anybody know if that procedure should be 
applied on the 4600?    The documentation that came with the machine did not 
mention it.

As a possible alternative I can buy a PC133 version of the 256 MB SODIMM for 
a reasonable price on Ebay but the PC is a PC100 machine - would the faster 
SODIMM actually work at the slower speed?

TIA
Malcolm 

Yes. Try ONLY the 2nd slot.



Sounds most unlikely.



Of course. The speed is a maximum. That's not the compatibility
problem.  Not all pc133 and pc100 mixes are compatible.  It's all sdram,
however.

Peter

Thanks Peter, I will try 2nd slot only before anything else.

This is the source of the info on "Fn + F3" routine:

 http://www.**--****.com/ 

- accessed via a link to "Memory Installation Guides" - Toshiba.    There 
seems to be no guide specifically for the 4600, so it could well be 
different.

You say that the maximum speed should be no problem in this case, but you 
also say that "not all pc 133 and pc 100 mixes are compatible" - are there 
other compatibility issues that I might encounter?    I will only buy a 
single 256MB (pc 133) stick if I cannot get both of the current 128 MB 
sticks working, so the system will only end up with either 2 x PC 100 
SODIMMS or one pc 133 one, so the "mix" shouldn't be an issue should it? 
Of course, if I end up getting the 256 item I may well try putting one of 
the 128's in the second slot, but I am guessing that you are suggesting that 
this may be a problem - is that right?

Thanks for shedding light in the darkness ;-)

I don't know what entry there you mean, but I assume that they simply
want to make sure you are BOOTING the computer rather than, for example,
returning from hibernation.  You surely can't fall for that one!


Sure - any and all. Pc100 and pc100 is not always compatible either!


No it's not :-). I am not suggesting anything - merely pointing out that
compatibility issues are always possible, unless you match the memory
carefully... that is not to say they are likely.

Peter

LOL!

No I wouldn't fall for the old "I'm hibernating but he thinks I'm switched 
off" routine - the oldest trick in the book (as M. Smart was wont to say) - 
but the actual PDF that I read it in was this one:

 http://www.**--****.com/ 

It refers to a "Satellite" series laptop, but a pretty old model, and I 
think that they are just making sure that it's not actually defaulted to 
Hibernate - so not relevant in my case.    I just wanted to be sure that 
there was no routine required to force the BIOS to check for additional 
memory - I guess the answer is "no" it should be autodetected at every boot 
up.    Back to a hardware issue and suck-it-and-see I think.

Thanks for the assistance.

I don't accept that your Fn+F3 procedure is necessary or relevant.

And, as someone else suggested, try JUST one module that you know works 
in that machine in the socket that you suspect is bad.

In and of itself, PC133 memory will work at PC100, but that is not the 
entire issue.  Most PC133 memory is newer than most PC100 memory.  And 
most newer memory has a newer internal chip architecture which may be 
incompatible with an older chipset designed for PC100.  The issue is the 
internal chip and module architecture, not the speed (PC100 vs. PC133) 
per se, but that doesn't change the fact that a lot of [newer] PC133 
memory won't work in [older] systems using a chipset designed for PC100 
memory.

It is very common that in machines with two memory slots, the modules 
installed in the two slots need to be of a similar internal architecture 
or the combination won't work, even though both modules are good and 
either will work by itself.  There is more to a memory module than size 
and "speed" (PC100 or PC133).

There is no action required when adding memory to a Toshiba.  I service 
Toshiba laptops, and have never run into such an issue in any model.

Thanks for the helpful information Barry.