On Wednesday November 20 2002 11:42 am, Anne Wilson wrote:
> On Wednesday 20 Nov 2002 3:55 pm, Technoslick wrote:
> > From: "Anne Wilson"
> > The external bus speed on a 233 MHz processor is 66.6
> > MHz, so I would think that you should be able to use PC133 memory.
Ram is what it'll do. The PC66, 100, 133, etc. labels are just
that, marketing labels. My daughter is usin a pc (for years now) with
ancient generic 66mhz ram runnin at 112mhz, Cas3 (PII-350 at 392, Aopen
mobo). It'll pass memtest86 at 133mhz, Cas3. Twice it's 'label' ;>
The system I'm typing on is usin 5 year old pc100 at 135mhz, Cas2 (1.4
Tbird at 1.55gig, Soyo), mixed with two other Crucial pc133 sticks
(7.5ns, Cas2). They all get a steady 3.45v IO from the Soyo and
Sparkle power supply, APC UPS.
Quality ram is important, but even the best ram won't perform
properly on marginal (cheap) motherboards. In many systems the
motherboard is more important than the ram's rating for optimal, or
even just adequate memory performance. Ram is more properly spec'd in
terms of ns and Cas rating and the quality and design of the pcb (the
card) the ram chips are on. As always the power supply is also a _very_
important element.
FWIW, the old pc100 will pass memtest86 runnin forever at 155mhz
Cas3, -0- errors on a Soyo (6ba+III, 3.5v IO). It was labeled pc100,
but it's quality Mosel Vitelic 8ns Cas2 ram. To figure what ram is
needed (assuming a good mobo and psu), take 1000 divided by the FSB
speed. EG, 1000/155 = 6.45. So that old pc100 was runnin at 6.45ns
when it blew by the memtest86 tests flawlessly ;) For DDR sdram
(another marketing gimick) use one half, EG, pc2700, 266mhz ram really
runs at 133mhz. So 1000/133 = 7.5ns. Cas isn't as important. Altho
theorectically it addresses in 2/3's the cycles, the real world
enhancement is about 5 to 7%. I'd advise to always buy Cas2 rated ram
tho.
So, ram is what it'll do. 'Sides it doesn't determine how it's
timed, the motherboard does (bios settings, IO voltage, capacitors),
and it needs steady, clean power.
--
Tom Brinkman Corpus Christi, Texas
Want to buy your Pack or Services from MandrakeSoft?
Go to http://www.mandrakestore.com
