Question about Athlon 200 Mhz vs 266 Mhz...

[jtbuzek]

I have a 750 Duron running on a Shuttle AK12. This board does not support the new 266 System Bus Athlon CPUs (as far as I know). Does this mean that I can't use an Athlon with 266 System Bus, or that the Athlon will simply function as the 200 System Bus this board can support? Please help me out on this one - I noticed that the 266 System Bus Athlon CPUs are selling cheaper than the older 200 System Bus ones.

Thanks,
James

 

[Boonesmi]

i dont know any thing about your motherboard, but.. assuming it only supports 100mhz bus, and that it does have multiplier adjusment, then you can buy the (266) parts, unlock them and change the multiplier

example
1ghz(200) is 100mhz x 10x multiplier
1ghz(266) is 133mhz x 7.5x multipier

if you buy a 1ghz (266) you can unlock it and change the multiplier to 10x then run it at 1ghz on your 100mhz board

edit oops a typo

 

[Peridium]

The difference between the 200MHz FSB and the 266MHz FSB is that they have a different multiplier to accomodate the bus speed differences. You could always adjust the multiplier manually to whatever you needed. You shouldn't have any troubles using a 266MHz FSB Athlon on your board. Just adjust the multiplier to compensate the decrease in the bus speed.

eg.
1GHz 200MHz FSB Athlon = 10 X 100
1GHz 266MHz FSB Athlon = 7.5 X 133

Edit: Doh!, Boonesmi beat me to it.

 

[Garet Jax]

jtbuzek,

Something that isn't explicit about the previous two posts is that if you buy a 1.0GHz 266 Athlon CPU (7.5 X 133) and you run it on a system with only a 100MHz FSB, then your CPU will only run at 750MHz (7.5 X 100) unless you unlock it (ie. you will need to unlock to run at 1.0GHz). In this case, it is almost easier to buy a 200 Athlon CPU. That way you won't need to unlock it.

 

[jtbuzek]

Thank you very much for the help guys. As I am obviously not a hardware guru, it does seem easier to just pay a little more for the 200 Mhz Athlon, that way I don't have to do anything out of the ordinary to use it. I believe the motherboard auto detects the CPU and adjusts the voltage (or maybe I have to switch a jumper or two), either way it seems easier. Again, thanks for the great help. I love this Anandtech forum.

James