I am unhappy with the apparent speed at which my laptop runs: WinXP SP2, HP Pavilion ze4523, Intel Celeron 2.4GHz, 256MB RAM. I feel inadequate. I want to try Ubuntu, but my computer is too slow.

The HP Service manual says I can have up to 1GB using 512 SDRAM modules. That seems more like it. However, it says PC2100 DDR-266 SDRAM. When talking about User-Replaceable SDRAM modules, the Service Manual lists a variety of HP and Compaq machines that can only use DDR266 SDRAM modules, but this does not include my ze4500.

I'm wondering if it's possible to use any type of laptop RAM, or if I'm limited to DDR266. Even better, could I use DDR2? It is cheaper, but most of what's available at my local computer store is DDR2-533 or -667. Am I correct in thinking that DDR-333 or -400 will work in my laptop, but be limited by the bus speed? The service manual mentions 266MHz processor system bus.

Perhaps a little explanation about hardware would also be good. Thanks for any replies.

DDR PC 2700
http://www.crucial.com/

Thankyou very much. Pretty good site - better than my local, Price Spy

Cheers.

Following is part of a cpuz.txt file that I created today. I have bought two G-skill 512MB DDR400 modules for my laptop, seemed like the best deal at a local store. The crucial link above said it was possible to run DDR333 PC2700 or DDR400 PC3200 modules. They aren't recognised - computer doesn't boot with only one or both of them in, but does run on the original 256MB module, and cpuz physically finds a new one.

Have I outdone myself? Does the module I bought only run with 166 or 200 MHz, according to the timings table? I was quite careful with static. Anyone want to buy a couple of laptop memory modules for cheap?


Memory SPD
------------------------------------------------------------------------------

DIMM #1

General
Memory type DDR
Manufacturer (ID) (FFFFFFFFFFFFFFFF)
Size 256 MBytes
Max bandwidth PC2100 (133 MHz)
Part number FC5BD404
Serial number FFFFFFFF
Manufacturing date Week 255/Year 255

Attributes
Number of banks 2
Data width 64 bits
Correction None
Registered no
Buffered no
Nominal Voltage 2.50 Volts
EPP no
XMP no

Timings table
Frequency (MHz) 133
CAS# 2.5
RAS# to CAS# delay 3
RAS# Precharge 3
TRAS 6


DIMM #2

General
Memory type DDR
Manufacturer (ID) G.Skill (7F7F7F7FCD000000)
Size 512 MBytes
Max bandwidth PC3200 (200 MHz)
Part number F1-3200PHU1-512SA

Attributes
Number of banks 1
Data width 64 bits
Correction None
Registered no
Buffered no
Nominal Voltage 2.50 Volts
EPP no
XMP no

Timings table
Frequency (MHz) 166 200
CAS# 2.5 3.0
RAS# to CAS# delay 3 4
RAS# Precharge 3 4
TRAS 7 8