A friend has an Evorex PC which has a problem with its 256Mb RAM chip (PC keeps freezing). I think the chip is SDRAM 133. I have 2 spare SDRAM 100 chips which fit and seem to work OK. Will this damage either the PC or my RAM chips?

Many thanks.

Simpson

No!

- so long as the FSB is set to 100 and your not trying to run the RAM at 133Mhz.

May be worth checking what his voltage settings are in case he's tweaked his PC.

Thanks pal. The RAM 133 is orginal as fitted by Evorex so I don't think there are any unknown tweaks - his knowledge is even less than mine! Please enlighten me as to what is FSB and where I would find its settings and also where I would find the voltage settings just in case. If all is OK will 512Mb 100 RAM still be preferable to 256Mb 133 RAM?

Simpson

The memory shouldn't run slower than the processor. If your friend has a modern processor (e.g. 733MHz or above), then it's likely than it's running at a multiplier of 133MHz - that means it's a 133MHz Front Side Bus (FSB) and you should run 133MHz SDRAM.

However, HippyWarlock has suggested that, if this is the case, you could go into the BIOS (or change a jumper pin setting on the motherboard) and slow down the processor so that it runs at a multiplier of 100MHz instead.

If that still doesn't make sense, we'll need to know the processor that is in your friend's PC, e.g. "Intel Pentium III 733MHz model SY087" or something like that. Of course, you might be able to work out the FSB yourself - a processor speed ending in 33 or 66 will always be 133MHz.

Thanks for the timely tutorial. When you say "shouldn't run slower than the processor" do you mean "musn't" or can I give 512Mb of PC 100 RAM a try to see if it's preferable to 256Mb PC 133 RAM? Sorry to ask what might be the obvious but learning all the time!

Simpson

lol, you're welcome to try it but the PC100 memory ought to cause the system to crash quite a lot, which the PC133 memory wouldn't..... unless you slow the processor down. Won't cause any lasting damage though.

Also note that you might be able to get the processor to run at 100MHz FSB instead of 133MHz FSB but increase the multiplier by an appropriate amount so that the processor's overall speed is actually similar to what it was before.