which DDR memory to get?

[Patrick]

Hello,


I just bought a new motherboard (Chaintech 9VIF1, see specs below) and a 2.5
Ghz Celeron. According to the specs, it takes PC1600 or PC2100 memory.
From what I gather, a PC2100 module corresponds to a 266 MHz bus speed.

However, the specs for this motherboard also indicate that it will take
either an Intel P4/Celeron@400 MHz or a P4/Celeron@533MHz.

Can somebody please explain this all to me?

Thanks,
Patrick
______________________________


Specifications:
Processor Interface: Socket 478
Processors Supported:
- Intel Celeron @ 400MHz
- Intel Celeron @ 533MHz
- Intel Pentium 4 @ 400MHz
- Intel Pentium 4 @ 533MHz
Chipset:
- VIA P4M266A Northbridge
- VIA VT8235 Southbridge
Front Side Bus:
- 400 MHZ
- 533 MHZ
Memory:
- 2 184-Pin Memory Slots
- 2GB Maximum Memory Supported
- Supports PC1600/2100 DDR SDRAM modules

[daytripper]

On Thu, 18 Dec 2003 09:40:44 GMT, "Patrick"
<infospecter@mindsrping.com.NOSPAM> wrote:
Hello,I just bought a new motherboard (Chaintech 9VIF1, see specs below) and a 2.5Ghz Celeron. According to the specs, it takes PC1600 or PC2100 memory.From what I gather, a PC2100 module corresponds to a 266 MHz bus speed.However, the specs for this motherboard also indicate that it will takeeither an Intel P4/Celeron@400 MHz or a P4/Celeron@533MHz.Can somebody please explain this all to me?Thanks,Patrick______________________________Specifications:Processor Interface: Socket 478Processors Supported:- Intel Celeron @ 400MHz- Intel Celeron @ 533MHz- Intel Pentium 4 @ 400MHz- Intel Pentium 4 @ 533MHzChipset:- VIA P4M266A Northbridge- VIA VT8235 SouthbridgeFront Side Bus:- 400 MHZ- 533 MHZMemory:- 2 184-Pin Memory Slots- 2GB Maximum Memory Supported- Supports PC1600/2100 DDR SDRAM modules

You don't ask for much, eh? ;-)

OK, quick 'n' dirty (and coached in non-controversial metrics ;-):

PC1600 = 8 bytes per dataphase @200megaphases per second
Based on a 100mhz clock

PC2100 = 8 bytes per dataphase @266megaphases per second (<=more bandwidth)
Based on a 133mhz clock

The Celly and P4 @400 are based on a 100mhz clock, and require at least PC1600
dimms, but - depending on the chipset abilities - may be able to take (some)
advantage of PC2100 (I don't know the VIA chipset but my guess is it *will*
exploit PC2100).

The Celly and P4 @533 are based on a 133mhz clock, and will do best with
PC2100 dimms, but will probably work with PC1600 (again, subject to the VIA
chipset capabilities - but this kind of flexibility is a PacRim engineering
staple, so I'd be surprised if it *didn't* allow using the slower memory).

Bottom line: the Celly/P4 @533 using PC2100 memory would be the best you can
do with your choices...

/daytripper