Merch,
I went through a DEEP cost basis analysis to get most performance
gains on each technologies:
EDO, FPM and hd's up to Fast ATA-2, HX with PB 512k gives best bang
and no improvement in performance without eating too much $ if using
SDRAM with that brain-damaged VX or TX chipset especially only with
P5 class. Too many new P5 pc's are selling with 32mb or over
installed therefore VX and TX is out. TX make good short term
upgrade mobo if spending under 600 bux for hd/mb/mem/cpu/PCI vid
package.
Best use for SDRAM's Dimm's are for the PPro/P5II with FX/LX440
chipsets, and Ultra ATA hds types. Yes, there's PPro adapter board
to plug into Slot 1.
That done and put aside...about timings;
Note this one: 5-1-1-1 and SDRAM technologies:
And I hasten to correct a bit about 10ns part...the first part
setting up one address takes exactly as long as normal FPM or EDO
does to get data back is between 60-50ns which is why the first few
cpu cycles is 5 cycles. Without changing the original address,
if cpu needs next instruction at that next address from old one the
SDRAM made data available the instant CAS is either on rising or
falling the next address location is ready to be read for cpu one
cycle later, same thing for next 2 cycles later for getting next 2
datas. Also and along that if there is a page cache hit, it's 10ns.
Miss is regular old DRAM performance.
The possible total true 0 wait with interlaving banks memory with
that fastest available typical FPM or EDO is 45-50ns which is appox
less than 25mhz for 486 and below. That is why I insist rather
strongly to new buyers to take branded pc's that must have fully
configured cache and QUESTION the spec paper if cannot see the
featured cache when looking at pcs on display.
Due to massive amounts of caffeine & sleep
deprivation, Hotze said:
Ranting of wishful thought snipped!
Ah, yes... but EDO is nowhere near the fastest!!!
Check out a Computer
Shopper if you can get them... advertisers there offer SDRAM DIMMs
(168-pin) as fast as 10ns. (not a typo...)
Just make sure you get a motherboard with at least one DIMM slot, and
you're zoomin'.
HTH,
"Merch"
--
Roger Merchberger | Why does Hershey's put nutritional
Programmer, NorthernWay | information on their candy bar wrappers
zmerch(a)northernway.net | when there's no nutritional value within?
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