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Guest Henri W

MOBO & RAM Issues

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Hi all,I was checking out my MOBO's manual(ASUS P3B-F) and read the following: "For the the system CPU to operate at 100mhz, use only PC100-compliant DIMMs. When this motherboard operates at 100mhz, most system WILL NOT EVEN BOOT if non-compliant modules are used"Does this mean that I would not be able to use PC-133 mhz CAS2 DIMM modules along with this motherboard or is there an option for... who knows... some "tweaking"???Thanks,Jean.

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Warnings like these usually apply only to using lower rated DIMMS. I should think you could use PC-133 in the place of PC-100, and without any tweaking.-Basil

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You could get PC-133 SDRAM but because your mobo will only has support for Pc-100 ram , your ram will only run at 100hz even if you have PC-133. You need to have a mobo that will except pc-133 by default. You can still use the PC-133 ram it will only run at 100hz though Capt.Richard Dillon (KATL)www.jetstarairlines.comhttp://hifi.avsim.net/activesky/images/wxrebeta.jpghttp://jdtllc.com/images/RCsupporter.jpg"Lets Roll" 9/11 -----------------------Specs AMD 2400 XP MSI KTV4 512MB DDR 2100Asus GF4 ti 4200 128MBSB Audigy Gamer Ch Products Yoke and Pedals(usb)Windows 2000 Serivce Pack 3

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Jean..My PC-133 RAM is running at 66 MHz right now because of my 500 Cel/66 FSB, and when I take that out and put in the 1.4/100 Cel, I will then set my FSB to 100 MHz. If I put in the Pentium III 1.4/133 , I'd set it for 133 MHz.You should not have a problem.Cheers!Mitch R.

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Hi Mitch,That is the exactly kind of RAM that you've placed into your sys, am I right?But if I do that, I won't be able to get the most out of the RAM like you did, will I??Thanks again,Jean.

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I would imagine that you would, Jean.Let me put it another way. Because I now have PC-133 Mhz rated RAM in my system rather than two sticks of 128 PC-100 RAM that I replaced...I now have the ability to run a Pentium III which runs stock at 133 Front Side Band. If I had only replaced my old generic PC-100 with higher spec PC-100, then I'd not be able to (by spec) run a Pentium III (133) FSB CPU. Why? The RAM would not be spec'ed to the Pentium III's native Mhz of 133.Also...funny how it is...but a stick (at Crucial Memory) of PC-133 right now is CHEAPER in price than a stick of equal quailty PC-100. What is happening here, is supply and demand. There is presently more PC-133 Mhz RAM than there is PC-100 MHz RAM. Hence, the cheaper price for the PC-133 AT PRESENT. It could change this minute with an update to their website. Cheers!Mitch R.

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Thanks for answering Mitch,Also inside my MOBO's manual short after the quote I've posted, it says that "if your DIMMs are not PC100-compliant, set the CPU bus freq to 66mhz RAM to ensure system stability". I see that in your Celeron 500mhz you did set the freq to 66mhz haven't you, or did I get it wrong??? So I think that is my case... But tell me, when you posted early that you got a booast in performance... did that happened with your old 500mhz(even having to set the bus freq to 66mhz) or only when you changed your processor and BIOs???Thanks again and sorry to bother you so much,Jean.

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Jean,You have an older motherboard from the era (not that long ago) when PC-100 DIMMS were the latest and greatest. Things have come quite a ways since then. Rest easy that the PC-133 DIMM modules will work well and support a 100 MHz bus speed (after all, they are qualified to support up to a 133 MHz bus speed).Don S.Mitch - so put in that new 1.4 Celeron already!

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Don...lol, I've been trying to find a place that has the Arctic Silver thermal grease. I'm going to be snoopin' around with my girlfriend through some shops today...some of hers...and some of (heh, heh) MINE!If the #@Y@*# Silver can't be found..I'll admit defeat and go to Radio Shack for whatever they have...lol. I'll slap that puppy into the slot, don't you worry. It's clearing its throat on the dining room table in boredom...(wink).I've got this sucker(system) tuned and giving me stable 15's with the lowly 500!!! Life is grand, bud...life is just grand....LOLOLOLI bet you that as soon as the U.S. declares war upon Iran... system memory will go through the roof again...anything that has an oil base to its manufacture. You just watch. Upgrade parts will do just that, upgrade in price.... Everything will...sadly....Now is the time to upgrade, if at all....not later...My opinion of course, and others opinion-milage will vary, ;)Mitch

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Jean,This is exactly what I have been struggeling with since yesterday. I have a P2B-F MoBo (with latest BIOS) and was using 2 x 128 Mb PC-100 SDRAM. I wanted to increase my memory. Prices for PC-133 RAM are cheaper nowadys than PC-100, so yesterday I decided to add 256 Mb of PC-133 RAM. Did it work? Well, partly. My PC only recognized 128 Mb of the added 256 Mb RAM. This is a well known issue, when using PC-133 Dimms with a PC-100 MoBo. I just returned the PC-133 Dimm to the shop and installed a PC-100 version instead. This works as advertized. I also had the impression that my system was stuttering a bit when using the PC-133 RAM in addition to the PC-100 Dimms I already had.Of course, I do not know how things work with the P3B-F, but be prepared to seeing the problem I discovered.Best regards,Henrihttp://hifi.avsim.net/activesky/images/wxrebeta.jpg

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By the sound of your post, I think I understand that you added a PC-133 Mhz to the PC-100 Mhz you already had.Uh...you can't do that...You would have had to put two DIMMS of the SAME kind for the system to work. It saw only the first type and posted that as the 'only one'.Again..you can't mix n' match.When I upgraded, I took out my two PC-100 Mhz DIMMS and installed the two Crucial PC-133's that I ordered.Mitch R.

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