Anyone tried to upgrade laptop memory?

[haobo]

I bought a Compaq N400C last week and try to upgrade the memory to 384MB (originally 128MB+256MB).

The memory I bought is PNY N256S133Z. Amazon said it is PC100 so I bought it because my N400C requires PC100. But when I got the memory today I noticed it is PC133. I inserted the memory, started the laptop, everything is OK, bios can test the memory. But when the Windows XP started, an error message "missing or corrupt /SYSTEM32/DRIVERS/pci.sys" appeared, and the machine stopped there. If take the memory out and try another 128MB PNY memory, everything is OK.

Is PC133 compatible with PC100? Is there any requirement that 256MB chip must be inserted in bank0 and 128MB chip in bank1?

Thanks a lot for any help.

 

[ai42]

PC133 can run at PC100 speed, but not the other way around.

As far as reqirements per slot etc there shouldn't be but it is possible

 

[BlueWeasel]

Some PC100 memory can possibly run at PC133 speeds, but only the best brands do this and its a long shot even then...

 

[IanthePez]

try switching the memory slots?

 

[haobo]

The error message seems strange. I update my WindowsXP to service pack 1. But still "missing or corrupt /SYSTEM32/DRIVERS/pci.sys". It works fine if I use another 128MB PNY memory (PC100).

PC133 can cause PCI problem? That's funny!

 

[ai42]

Well what could take account is perhaps the slower memory is clocking down the FSB. So most likey the dividers/multipliers are locked across the entire laptop. Therefore you get an error because the PCI bus is being run at an incorrect speed, and since the multiplers are locked it can't really do anything about it.

 

[PH0ENIX]

Haobo;
You are correct - your N400C is a 100mhz machine.

With laptops the speed designation is slightly more important. Although PC133 will scale down to PC100 on most system - this is just not the case with 90% of notebooks, especially tier-1 machines. It's a more prominent issue attempting to put PC100 into older 66mhz machines, but it's still apparent when dealing with 133/100 like yourself.

The Kingston part number for the memory you require is KTC311/xxx where 'xxx' is the size in mb, so if you find a compatible part to that, you should be right.

Yes, I do an awful lot of laptop memory upgrades.

Just my.02,

Ph0.

 

[haobo]

Cool ai42, you are guru.

Now I'm trying to install a PC133 memory module on a PC100 laptop. PNY said PC133 is backward compatible with PC100, "but not to all laptop:-----("

It seems N400C cannot support PC133

 

[SexyK]

You guys aren't reading his post right, he's trying to run PC133 memory in a PC100 system. It should work fine, I suspect that there's a problem more with the ammount of memory than the speed. It works with a 128MB in there, but not a 256MB. Maybe there is a limitation at 256MB total or something? check the specs on your laptop and see what the max supported RAM is.

Kramer

EDIT
From the Compaq Website

Memory
Standard 128-MB SDRAM

Maximum 512-MB SDRAM (with two slots)

NOTE: Due to the non-industry standard nature of some third-party memory modules, we strongly recommend using only Compaq branded memory modules to ensure compatibility.
NOTE: 256-MB and 512-MB 133-MHz memory are not compatible with the Evo Notebook N400c.

There's your answer, looks like you should go to Compaq and get their memory.

 

[haobo]

Thank you, PH0ENIX. Someone is trying to persuade me to change my 256MB PC133 for his 128MB PC100

In the bios the system can correctly recognize the memory. Does it mean I can get it work by some means of software upgrade? I don't want to give up my 256MB memory.

 

[haobo]

Well, finally SexyK quenched my hopes.

I'll return it to Amazon tomorrow morning. They said it is PC100 but sent me PC133.

Thank you all. Here is the rite place and I meet rite ppl.

 

[Mingon]

It could have been the cas latency - perhaps the pc100 was cas 2 and the pc133 was cas 3, why not just use crucial.com

 

[PH0ENIX]

Tru, 133 isn't.

Industry Standard 100mhz SODIMMS are, however.

To answer your question w/ regard to memory detection - as a general rule if it's not going to work correctly it wont even show the extra. But because architecturally the PC100 and PC133 modules are quite similar - it may be that the machine doesn't have a problem READING the memory - but when writes are involved it all goes pear shaped.

The answer is likely a tad more complex - but that gives you an idea.

Dont worry about compaq genuine brand. It's great stuff but it's just not cost-effective and besides ASSURED compatibility it isn't any better.

Industry std PC100 SODIMM is what you need