View Full Version : RAM question...PC100 and PC133

12-30-00, 01:30 AM
Is it possible to mix PC100 and PC133 RAM on the same motherboard? My motherboard right now only supports PC100, so if i mix the RAM, will this cause any problems?


12-30-00, 01:32 AM
it might, it might not

I am doing it with 2 different models of ASUS mobo.....

12-30-00, 01:57 AM
Yes, probably so. The PC133 will just be run at 100. What motherboard and CPU do you have?

12-30-00, 02:34 AM
My motherboard is an Asus 440BX and my CPU is a Pentium 3 450 MHz.

I just tried adding an additional 128 Mb of PC133 RAM to my motherboard. Everything seems to be working fine....for now.

I hope my computer doesn't go wacko one unsuspecting day.

12-31-00, 04:08 PM
I have used both for two years have not had a problem. Like it was said the board proubly adjust them. PC100 and Pc133 128mgh in my system total 256

01-01-01, 07:01 PM
Im not really clear on all this PC-100, 133, 66, ect. I am thinking it means the type of ram that was made for a certain cache size, like a celeron is a 66 so my ram is pc-66? Now I bought a celeron but a mother board capable of upgrade to say a p3, so im wondering if I should buy what new ram I get as pc-133, so that way I can still use it when I get my p3? Will pc-133 work for my system? Pc-66 wouldnt work for a pentium tho right? If someone could clear this up for me, thanks abunch.

01-01-01, 07:35 PM
Hi guys
No need to worry about this memory issue http://www.speedguide.net/ubb/smile.gif With all recent motherboards you don't need to touch the bus speeds and you can mix and match the momory e.g 2x64(100) 1x128(133).
All that will happen is that the bus will run at the lowest chip speed (so in this case 256mb running at 100) so it doesn't matter how much memory you put in, it will still run at the lowest speed. But to be honest, you shouldn't see much diffence between 100 & 133, but you would between using 64mb and 128mb.
Hope this helps


01-01-01, 08:31 PM
I noticed a large difference in Win2k performance when I bumped my memory speed up to 140 from 100.