FSB 800/533

[demetrics]

On a lot of motherboards I see 800/533 for the FSB. So how does the motherboard determine which one it is going to use? Is it by the RAM? IF I put in DDR400 will it use 800(for the optimal performance of the ram and FSB both running at 200MHZ)? IF I put in DDR 533(which is a faster RAM) will it USE the FSB533, which is a slower FSB for optimal performance? Thanks

 

[MrBLUNT]

1. 800fsb is faster than 533fsb
2. for 800fsb, u need atleast 400mhz ram (ie pc3200)
3. for 533fsb, u need atleast 333mhz ram (ie pc2700) or 266mhz (ie pc2100)

even if u use faster ram, u will not achieve higher fsb unless u overclock it.

 

[Concillian]

On the Intel platforms,
FSB is like DDR memory, it runs at one speed and they quote the 'effective speed' 533 is really a 133MHz FSB (133x4 = 533)

So 533 uses 133 MHz memory (PC2100) and 800 uses 200 MHz memory(PC3200)

The motherboard detects the FSB based on the PROCESSOR you put in it. a P2.4A will run 133x18 a 2.4C will run 200x12. Most motherboards allow you to set the FSB in BIOS to values in between 133 and 200. In doing so on a 533MHz FSB processor you'd be overclocking it, since the multiplier CANNOT be changed.