Mixing SDRAM of different Memory Timings ?

[varunmehta11]

I have an HP Pavilion 8505 Desktop. Recently i upgraded its memory to 384 MB. What i've done is that i added two more 128 MB SDRAM modules to my current 128 MB SDRAM Module.
But the new RAM sticks are of 100 Mhz frequency and the old ram module is 133 Mhz. And when i checked in the EVEREST Ultimate Software Snapshot, i get details of the three RAM Modules that : The two new RAM modules have two memory timings of 83 Mhz and 100 Mhz and the old Memory module has memory timings of 83 Mhz and 133 Mhz. Does that mean that the three memories would be down clocked to 83 Mhz instead of 100 Mhz (since the old RAM is not showing 100 Mhz support in the Memory Timing details) ? Will there be any Performance decrease or any malfunctioning. Nevertheless my PC is recognizing the whole 384 MB Memory in the BIOS.
Also the Processor FSB is 100 Mhz.

My PC Config :
Intel Pentium III 450 Mhz
384 MB SDRAM
100 Mhz FSB
Windows XP Pro SP3

 

[varunmehta11]

still there are doubts in my mind, why the EVEREST is showing the memory timings of the old SDRAM at 83 and 133 Mhz only and not at 100 Mhz. Does that mean it cannot work at 100 Mhz ? is it downclocking all the RAM modules to 83 Mhz or is it not at all functioning while still showing 384 mb system Memory ?

 

[Denithor]

It should all run at 100MHz.

Use CPU-Z to check speeds.

 

[Blain]

There are no 83MHz modules.

There are...
66MHz, 100MHz, 133MHz, 150MHz and even 166MHz

All your DIMMs are running at 83MHz because the MB isn't defaulting correctly or has been set wrong in the BIOS.

 

[varunmehta11]

CPU-Z is showing the FSBRAM ratio as 1:1 i.e. 100 Mhz. Does this verify that all the RAM modules are functioning properly at 100 Mhz ?