Ram Query

[myf360f1]

Hi Guys,

I have gotan ASUS lappy A9RP series 1.8Ghz and it came with 512Mb ram std. At the time I asked to be upgraded to 1Gb and it was done, however I have always felt that it was never right. On one program it would say that I had 895Mb ram.

So I ran cpuid and my results were:

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

DIMM #1

General
Memory type DDR2
Module format SO-DIMM
Manufacturer (ID) Qimonda (7F7F7F7F7F510000)
Size 512 MBytes
Max bandwidth PC2-5300 (333 MHz)
Part number 64T64020HDL3SB
Serial number 03132211
Manufacturing date Week 02/Year 07

Attributes
Number of banks 2
Data width 64 bits
Correction None
Nominal Voltage 1.80 Volts
EPP no
XMP no

Timings table
Frequency (MHz) 200 266 333
CAS# 3.0 4.0 5.0
RAS# to CAS# delay 3 4 5
RAS# Precharge 3 4 5
TRAS 9 12 15
TRC 12 16 20

DIMM #2

General
Memory type DDR2
Module format SO-DIMM
Manufacturer (ID) (FFFFFFFFFFFFFFFF)
Size 512 MBytes
Max bandwidth PC2-5300 (333 MHz)
Part number GU33512AJEPN612L4G
Serial number FFFFFFFF
Manufacturing date Week 165/Year 165

Attributes
Number of banks 1
Data width 64 bits
Correction None
Nominal Voltage 1.80 Volts
EPP no
XMP no

Timings table
Frequency (MHz) 200 266 333
CAS# 3.0 4.0 5.0
RAS# to CAS# delay 3 4 5
RAS# Precharge 3 4 5
TRAS 9 12 15
TRC 12 16 20



So I pulled it apart and found I stick of ram that says PC2-5300s -555 and another stick that has DDR2-667 they were from different manufacturers.

So my question is what ram am I suppose to be running?
Why is it not dual channel?
If I upgrade to 2 x 1Gb shouldn't they be a matched pair?

Sorry but this stuff is a bit confusing.

Thanks in advance

[intelliGEORGE]

PC2-5300 is DDR2-667

[mandc]

Matched pairs of RAM is preferable but not essential. You get far fewer RAM issues if they are matched.
You probably already know this but the reading you get of only 895 Mb RAM is due to the shared RAM with your graphics card

[myf360f1]

Hi intelligeorge,

"PC2-5300 is DDR2-667" so why has it got the 333MHz what does this figure relate to?



Thanks Mandc that clears the matched question up.


Why does it say single channel and not dual like on my desktop?


Sorry guys one more question, is it better to upgrade to 2 x 1Gb or 1 x 2Gb ram ?

[mandc]

From wiki:
DDR2 SDRAM or double-data-rate two synchronous dynamic random access memory is a random access memory technology used for high speed storage of the working data of a computer or other digital electronic device.

It is a part of the SDRAM (synchronous dynamic random access memory) family of technologies, which is one of many DRAM (dynamic random access memory) implementations, and is an evolutionary improvement over its predecessor, DDR SDRAM.

Its primary benefit is the ability to operate the external data bus twice as fast as DDR SDRAM. This is achieved by improved bus signaling, and by operating the memory cells at half the clock rate (one quarter of the data transfer rate), rather than at the clock rate as in the original DDR. DDR2 memory at the same clock speed as DDR will provide the same bandwidth but markedly higher latency, providing worse performance.

333Mhz is the clock speed but it is doubled to 666 [667], hence DDR2-667


DDR2-667 clock=166 MHz I/O clock=333 MHz Data transfer rate=667 Million/sec Name=PC2-5300
peak transfer rate=5333 MB/s

[myf360f1]

Thanks mandc,

Any thoughts on my last question?

[mandc]

Hi intelligeorge,
is it better to upgrade to 2 x 1Gb or 1 x 2Gb ram ?

Whatever is cheaper.
You won't be able to fully use 4G on 32bit systems...vista or xp and on a laptop I would think 2G is heaps....Just my opinion of course!

[myf360f1]

Thank you Mandc, will follow your lead.

Cheers