Bus Clock 66

[eastfield]

I have two available memory slots Slot 0 and Slot 1. One slot is occupied with 64mB memory module.The bus clock is 66 mHz,the processor,333 mHz Intel Celeron processor,32Kb primary memory cache,128Kb secondary memory cache.

Do I need to buy memory modules for 66 bus clock speed or will my computer run faster with with 128mb,100PC or 128mb,133PC memory modules? Where can I source memory modules for 66 bus clock speed?

Eastfield

[OuTpaTienT]

Your computer will not run faster with pc100 or pc133 memory. You might compare this to putting high performance tires on a car. They don't make it go faster. They give it the ability to go faster, if it could, but they don't actually make it go faster.

Now, as far as you buying ram, you'd probably be best off buying pc66 ram if it's available and affordable. However almost all ram of this type is backwards compatible (pretty much). You can fairly safely assume that pc100 ram will work fine in a 66mhz bus. Supposedly, pc133 will also work at 66mhz, but I've seen a number of situations where that didn't happen. So don't count on pc133 working for ya.

Considering how quickly hardware grows out of date in the computer industry, you might very well find that pc100 ram is more easily available and even cheaper than pc66 ram. If that's the case, I'd go for the pc100 without hesitation.

Any ram you put into your machine (be it pc66, pc100, or pc133) will all run at the bus speed of 66mhz.

If your motherboard has the option of setting the bus speed to 75mhz or more, then you might definitely want to get ram that's rated for speeds higher than 66mhz, this way you would have a better chance of achieving successful overclocking, if that's something you're willing to do.

Also, check to see if your motherboard uses ram that is 5volts or 3.3volts. Most likely it's 3.3v, but there were some motherboards of that 66mhz bus era that needed 5v ram. 5v and 3.3v ram are not interchangeable.

If I've forgotten anything important than I'm sure someone else will be along any minute to help fill you in. Don't go on my message alone...it's been quite a long time since I've been on a 66mhz bus.

[eastfield]

How do I go about changing the bus speed of the motherboard to 75 or 100mHz if the motherboard allows this ?

[OuTpaTienT]

Most likely there will be jumpers on the board that need to be changed to alter the bus speed. If you're lucky then maybe the board will be labelled clearly for what each jumper does. If not then you'll need to dig out your manual (or find it online) and see if the jumper configurations are listed.

Be aware there were plenty of motherboards with a max speed of 66mhz, so don't get your hopes up till you find out for sure.

[eastfield]

I will find out for sure and let ypu know.

[Cosmo99]

Me too......................
I'm working on my fathers computer and am wondering about the same thing.

I know his 64mb SDram chip is PC100 but all I can see available is PC133.

So is it ok to install a new PC133 128mb, Sdram chip beside his 64mb PC100 chip?

thanks

[eastfield]

It is OK however it will only run at 66 MHz.

[beppodmime]

In theory, all speed RAM of the same type is backwards compatible, i.e. PC133 will work fine at PC133 speeds, et cetera. But, in practice, mixing up speeds, especially if you're using generic memory, can lead to some problems. If you buy yourself a good brand memory (Crucial and Kingston come to mind, first), you should be ok. I have run a PC133 stick alongside my PC100 in my old Dell, and it worked just fine. However, mixing speeds of memory will cause the memory clock to the lowest common speed. If you throw in PC100 and PC66, it'll all work as PC66, and likewise for the rest of them. And none of them will work higher than the motherboard can support. So, even if you DO have a mobo that supports PC133, if you have even a single stick of PC66, it'll all need to run as PC66.