Need Memory for P4C800 Deluxe

[rfdjr1]

I'd like to but another Gb of memory for my system which is based on a P4C800
Deluxe board, P4 3.2 processor running Windows XP Pro. I currently have two 512
chips in the system. The information I see on those chips is:

512 Mb 32x8
PC3200
Infineon

I'm shopping online for another Gb and I find 512 chips at PC3200. What I'm not
sure of is if the speed of all PC3200 chips is 400? I guess what I'm asking is
what the DDR400 I see in the specs of chips I'm looking at means, as I see no
400 on the current chips.

Also, the manual for the board lists preferred chips for this board. How
critical is it if I can't find the exact ones they list? Will they work at all,
will there be a degradation of performance? And what should be a good price per
512Mb?

Thanks for any info. I plan on buying a matched set

 

[Roger Hamlett]

I'd like to but another Gb of memory for my system which is based on a
P4C800
Deluxe board, P4 3.2 processor running Windows XP Pro. I currently have
two 512
chips in the system. The information I see on those chips is:

512 Mb 32x8
PC3200
Infineon

I'm shopping online for another Gb and I find 512 chips at PC3200. What
I'm not
sure of is if the speed of all PC3200 chips is 400? I guess what I'm
asking is
what the DDR400 I see in the specs of chips I'm looking at means, as I
see no
400 on the current chips.

Basically yes. The 'PC' number, is the clock rate, times the 'width' of
the memory bus. The memory bus is 8 bytes wide, so memory clocked at 400M
transfers/second (actually 200MHz, but 'DDR' remember), transfer 8*400
Mbytes/sec = 3200.
However seperately, there are other 'specs', regarding how quickly other
transfers (the initial ones that set up the memory address) are done. Look
into your BIOS, and somewhere in the chipset settings, the 'memory speed'
will be being setup (normally 'by SPD', which involves reading these
timings from a small memory on the module). The commonest timings are
Cas3, Cas2.5, and Cas2, with the latter being 'faster' at doing these
setup transfers. You will find fast memories availble with this value
lower. Aim for at least the same performance in this area as the existing
units. Cas2.5, is the 'normal' value.

Also, the manual for the board lists preferred chips for this board. How
critical is it if I can't find the exact ones they list? Will they work
at all,
will there be a degradation of performance? And what should be a good
price per
512Mb?

On some boards, this is critical. On many it doesn't really matter at all
(just a list of units that have been 'tried'). Random reboots, memory
failures etc., are typical problems, but this type of behaviour has become
less common in recent years.
If you have a local shop, consider taking the machine 'in', and having
them fit the modules. For a tiny extra cost, you are then in the
advantageous position, that if there is a compatibility problem, they have
the problem, not you...

Thanks for any info. I plan on buying a matched set

Best Wishes

 

[rfdjr1]

Basically yes. The 'PC' number, is the clock rate, times the 'width' of
the memory bus. The memory bus is 8 bytes wide, so memory clocked at 400M
transfers/second (actually 200MHz, but 'DDR' remember), transfer 8*400
Mbytes/sec = 3200.
However seperately, there are other 'specs', regarding how quickly other
transfers (the initial ones that set up the memory address) are done. Look
into your BIOS, and somewhere in the chipset settings, the 'memory speed'
will be being setup (normally 'by SPD', which involves reading these
timings from a small memory on the module). The commonest timings are
Cas3, Cas2.5, and Cas2, with the latter being 'faster' at doing these
setup transfers. You will find fast memories availble with this value
lower. Aim for at least the same performance in this area as the existing
units. Cas2.5, is the 'normal' value.

On some boards, this is critical. On many it doesn't really matter at all
(just a list of units that have been 'tried'). Random reboots, memory
failures etc., are typical problems, but this type of behaviour has become
less common in recent years.
If you have a local shop, consider taking the machine 'in', and having
them fit the modules. For a tiny extra cost, you are then in the
advantageous position, that if there is a compatibility problem, they have
the problem, not you...

Thanks for that information. I checked the BIOS and under chipset all I see is a
choice to configure DRAM Timing by SPD, and it's set to enabled. The only other
choice is disabled. I can't find any reference to a Cas number. I did find
Kingston PC3200 512 chips which, according to their specs are designed for my
motherboard. Cost is fine for me at $50 a chip, which is half of what I paid a
year-and-a-half ago. My only other concern/question, is do I have to match the
two 512 modules I already have installed? That will probably be impossible. DO I
need to buy four of the same 512 chips or two more costl 1Gb chips? This machine
has run smooth since I built it and I don't want any problems. Would I be safe
with the Kingston memory I saw? I guess I Have to ask for a matched set or does
it matter? Thanks again