Deciding PC100 or PC133?

I don't know the big difference between the two. What kind of applications utilize PC133? What do you suggest and why?
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More about deciding pc100 pc133
  1. It's not really something that software takes advantage of, but more the availability of bandwith of loading and storing data to and from memory/cpu registers. It also tends to be the limiting factor in how high you can clock your FSB. PC133 CAS 2 is ideal for current processors, but DDR will over a 10% increase in performance very shortly. Or you can go with RDRAM if you anticipate upgrading to a P4 and feel like taking out a loan.
  2. Right now DDR is out of the question. My motherboard will only support up to PC133 RAM. It also supports ECC, but I read that isn't necessary unless your running a server.

    <P ID="edit"><FONT SIZE=-1><EM>Edited by foxnet3 on 11/11/00 10:29 PM.</EM></FONT></P>
  3. Not only that, but it's also expensive.
  4. Theoretically a pipe of 3" diameter will carry more water per sec compared to one with 2" diameter right? So PC133 will be faster than PC100. <i>Any</i> computer will take advantage of it, as long as your motherboard supports it.

    Morgan 1.6Ghz + 256DDR = Dream on
    However dreams are approacable :wink:
  5. Do all pc133 SDRAMs support CL2 (CAS LATENCY) ?
  6. one word: yes.

    Smart guys are not smart because they only see things at a different perspective. :wink:
  7. Depends on you motherboard, chipset and which CPU you have. If you have a Celeron which only uses a 66Mhz FSB and you aren't overclocking then PC100 will be fine. However, I recommend going with PC133 which is only a few $$ more and in case you wnat to upgrade in the future. Memory prices are pretty cheap right now. Crucial has 128MB PC133 CAS2 SDRAM for under $100 if you order off of thier website.
    As for CAS2 vs CAS3, CAS2 is slightly faster. I should also point out that if you mix different speeds, you can only go as fast as your slowest part.
  8. Where have you heard that? That's not correct at all. There are several PC133 sticks only supporting CAS3. (Belive me, I've tried.)
  9. The only difference is a little speed. 33mhz to be exact. Plus you need a 133mhz bus to coinside with the ram.

    "upgrading is no longer an's a necessity"
    --SoulReaper =)
  10. If you are going to buy the regular PC133 or PC100 dimms that every computershop sells, you'd probably notice that they are the same price. So then you can buy the PC133, cos they are PC100 compatible.

    If you are going to buy the faster brand dimms, then you'll notice a price difference. And then it´s just a question if you can afford it.

    And, do you need it? Can your mobo support it?
  11. BTW. about PC133 and PC100. If I have a Abit KT7 mainboard with Athlon 1100, then that motherboard supports PC133 but the Athlon actually double-pumps at 200 which should only demand PC100. What if I have PC133 CL3 memorys but clocks this as PC100 and CL2. It should work, I think. But what is the best setting? PC133 at CL3 or PC100 at CL2? Or, have I completely misjudged this ability?

    Best regards
    Bo Eriksson (Work) (private)
  12. PC100 at CAS2 is actually faster than PC133 at CAS3 when a 133 MHz memory bus next to a 100 MHz FSB is used. This is because PC133 will then run asynchronously, which on average adds half a clock cycle to the latency of the module. And with a clock cycle of 7.5 ns (PC133) instead of 10 ns (PC100), teh latency is already worse (22.5 ns for CAS3 PC133 against 20 ns for CAS2 PC100). And the wider bandwidth of the PC133 module is of no use when the data has to be fed to the 100 MHz CPU - besides the fact that latency is usually more important than bandwidth (see the Rambus drama)...
    Things are quite different if you have a 133 MHz CPU. And obviously even more so if you happen to have PC133 memory at CAS2. That's the best combination as long as DDR-SDRAM is not available.

    "I'm a stream of noughts and crosses in your R.A.M."
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