Crucial Memory

[Paul]

I have an A7N8X-X board and I've looked on the Crucial website for the
recommended RAM. 2 questions; 1) Can the Crucial memory selector be
relied on? 2) The price difference between PC2700 and PC3200 is negligible.
But the CL figure for the PC3200 is 3 while the CL for the PC2700 is 2.5.
I'm putting it in a system right now that only needs PC2700. If I run
PC3200 at a lower MHz I'll be comfortably able to set it at 2.5 - yes/no?

Thanks in advance

Paul

 

[Andrew J]

I have an A7N8X-X board and I've looked on the Crucial website for the
recommended RAM. 2 questions; 1) Can the Crucial memory selector be
relied on? 2) The price difference between PC2700 and PC3200 is negligible.
But the CL figure for the PC3200 is 3 while the CL for the PC2700 is 2.5.
I'm putting it in a system right now that only needs PC2700. If I run
PC3200 at a lower MHz I'll be comfortably able to set it at 2.5 - yes/no?

Thanks in advance

Paul

I would/do avoid Crucial on that board. While many have not had
trouble, many have. I don't know if it's 1 in 5, 1 in 10 or whatever.
There are 9 approved RAM types by ASUS for that board, and Crucial is
not on the list for a reason.


DIMM
Vendor | DIMM Part No. | CL | Size | Side | DIE
Vendor | DIE Part No.
Samsung | M368L6423
DTM-CC4 | 3 | 512MB | Double | Samsung | K4H560838D-
TCC4

Samsung | M368L3223
DTM-CC4 | 3 | 256MB | Single | Samsung | K4H560838D-
TCC4

Adata | BDMA83A | 2.5 | 256MB | Single | Winbond | W942508BH-5

TwinMOS | MDouble
TTUF08108L294
K4FW0/T | 2.5 | 256MB | Single | TwinMOS | TMD7608F
8E50B

Winbond | W9451GBDB-5 | 2.5 | 512MB | Double | Winbond | W942508BH-5

TwinMOS | | 2.5 | 512MB | Double | Winbond | W942508BH-5

TwinMOS | | 2.5 | 256MB | Single | Winbond | W942508BH-5

Kingston | KVR400X64
C25/256 | 2.5 | 256MB | Single | Winbond | W942508BH-5

Corsair | CMX512-3200C
2XMS3202 v1.1 | 2.5 |512M | Double | |

I run 2x 512MB Elixir in dual channel with no problems.
http://www.ms4me.com/mo51pc4ddrme.html

 

[James]

Isnt dual channel not supported on this board?

James

 

[S.Heenan]

I have an A7N8X-X board and I've looked on the Crucial website for the
recommended RAM. 2 questions; 1) Can the Crucial memory selector be
relied on? 2) The price difference between PC2700 and PC3200 is
negligible. But the CL figure for the PC3200 is 3 while the CL for
the PC2700 is 2.5. I'm putting it in a system right now that only
needs PC2700. If I run PC3200 at a lower MHz I'll be comfortably
able to set it at 2.5 - yes/no?

I've used the 512MB PC3200 modules in 20+ A7N8X-series boards. Provided you
run in sync with the FSB, disable SPD, and set RAM timings manually, I don't
forsee any problems. Yes, at some speeds between 166MHz and 200MHz you will
be able to run at CAS 2.5. Be familiar with how to perform a CMOS reset.

 

[DaveW]

No.

 

[Paul]

I have an A7N8X-X board and I've looked on the Crucial website for the
recommended RAM. 2 questions; 1) Can the Crucial memory selector be
relied on? 2) The price difference between PC2700 and PC3200 is negligible.
But the CL figure for the PC3200 is 3 while the CL for the PC2700 is 2.5.
I'm putting it in a system right now that only needs PC2700. If I run
PC3200 at a lower MHz I'll be comfortably able to set it at 2.5 - yes/no?

Thanks in advance

Paul

CL * Clock_Period = Cas_Latency_Internal

PC3200 = DDR400 = 200MHz Clock = 5ns, 5ns * CL3 = 15ns cas latency internal
PC2700 = DDR333 = 166MHz Clock = 6ns, 6ns * CL2.5 = 15ns

So, yes, a CL3 PC3200 becomes a CL2.5 at PC2700.

http://download.micron.com/pdf/datasheets/dram/ddr/256Mx4x8x16DDR.pdf

On page 58, under the "Clock cycle time" parameter, you can see the
product of CL * Clock_Period_min is a constant. I'm still looking for
examples of datasheets where this isn't true (like, I've been looking
for a datasheet on a Hynix DDR500 chip, type D5, as opposed to D43,
but I still cannot find one. The DDR500 datasheet would be interesting
because it would be a departure from the other "boiler plate"
style datasheets all the DDR ram makers use).

It is likely the two Crucial modules you are looking at, use very
similar chips. (One chip would be marked -6 and the other -5, but
the die inside could be the same die.) That would account for the
similar pricing.

Just some guesses,
Paul

 

[Ben Pope]

I have an A7N8X-X board and I've looked on the Crucial website for the
recommended RAM. 2 questions; 1) Can the Crucial memory selector be
relied on?

Yeah, and if not, they'll happily replace it.

2) The price difference between PC2700 and PC3200 is
negligible. But the CL figure for the PC3200 is 3 while the CL for the
PC2700 is 2.5. I'm putting it in a system right now that only needs
PC2700. If I run PC3200 at a lower MHz I'll be comfortably able to set
it at 2.5 - yes/no?

Not necessarily, but likely.

Ben