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ramu
08-07-2006, 10:17 PM
Hi There

I have just bought a mobo. The ad (trademe) said its FSB is 266. The Manual says its chipset is at 100/133 FSB and default setting is 133. My CPU is 266. Is this mobo going to give me 266 FSB at its default setting which is only 133? Or does it double automatically? If not, what should I do? Thanks.

tweak'e
08-07-2006, 10:27 PM
thats fine. 266 is 2x133 ie DDR :) on older mobo's make sure the ram is the same or faster than the FSB.

ramu
08-07-2006, 10:33 PM
Thanks Tewak'e. But can't we buy a mobo with the same FSB as CPU?
What is the 2x133 business. I don't understand. Sorry.

Jen
08-07-2006, 11:05 PM
Have a read of this article, it explains well - Understanding System Memory and CPU speeds: A layman's guide to the Front Side Bus (FSB) (http://www.directron.com/fsbguide.html) :)

tweak'e
08-07-2006, 11:06 PM
wheres your maths skills gone to ?? 2 x 133 = 266. DDR stand for Double Data Rate ie x2.

if in doubt simply post what mobo and cpu you have.

Vistra
09-07-2006, 02:12 AM
Hi ramu.

First of all (for your reading pleasure):
http://en.wikipedia.org/wiki/Front_side_bus

Secondly:
But can't we buy a mobo with the same FSB as CPU?

Yes, you can but motherboards that have the same FSB speed as the CPU, right now, most common Semprons are 533Mhz, AMD64 are 800Mhz and my new Fav is the AM2 AMD64 is 1000Mhz+ (1Ghz+) FSB.

Not sure if this helps but we did a job where we stuck a AMD BARTON CORE 2200+ into a 266Mhz FSB Motheboard (MAX), we had to set the FSB to 133Mhz even thought the motherboard could handle 266, because some CPU cores double the speed. I had a link explaining all of this, but I've lost it. It may have been because of the different Levels.....oh sorry, I dont remeber, it was a while back.

straitjacket
09-07-2006, 05:58 AM
Hi ramu.

First of all (for your reading pleasure):
http://en.wikipedia.org/wiki/Front_side_bus

Secondly:
But can't we buy a mobo with the same FSB as CPU?

Yes, you can but motherboards that have the same FSB speed as the CPU, right now, most common Semprons are 533Mhz, AMD64 are 800Mhz and my new Fav is the AM2 AMD64 is 1000Mhz+ (1Ghz+) FSB.

Not sure if this helps but we did a job where we stuck a AMD BARTON CORE 2200+ into a 266Mhz FSB Motheboard (MAX), we had to set the FSB to 133Mhz even thought the motherboard could handle 266, because some CPU cores double the speed. I had a link explaining all of this, but I've lost it. It may have been because of the different Levels.....oh sorry, I dont remeber, it was a while back.

Not sure but I think youre on drugs....first the semprons in the socket a range can only support 333 fsb.....ie 166 on clock frequency...the 754 semprons however have a 800mhz hypertransport and can support 400mhz ddr..the athlon64 in the 754 (which are not manufactured anymore) had 800 hypertransport and 400mhz ram ...ie 200 on clock.....the 939 athlon64 has 1000mhz hypertransport and can support 400mhz ddr the new am2 I believe still has 1000 hypertransport but can support up to ddr 2 800?? (I am not sure of that) and last but not least AMD NEVER MADE A BARTON CORE XP 2200+ the bartons started with the 2500+ or the XP-M series which started with a 2200 for mainstream and 2400 for the desktop replacements...a athlon xp 2200+ had to have been a thorton core or a thoroughbred core. and fore the recored if you set the cpu frequency to 133 that WOULD make the fsb 266 and would also set a 2200 at its correct speed of 1800 ....2200+ has a multiplier of 13.5 so 13.5*133= 1795.5Mhz and 133*2=266Mhz fsb does it not? So the moral of my story is I would never buy a computer from you!

ramu
09-07-2006, 09:20 AM
Have a read of this article, it explains well - Understanding System Memory and CPU speeds: A layman's guide to the Front Side Bus (FSB) (http://www.directron.com/fsbguide.html) :)


Thanks Jen.

ramu
09-07-2006, 09:25 AM
wheres your maths skills gone to ?? 2 x 133 = 266. DDR stand for Double Data Rate ie x2.

if in doubt simply post what mobo and cpu you have.


My maths skills are excellent but the point I had was:
How does the 133x2 calculation relate to the knowledge that the CPU will run at 266 FSB. This is 'cause there are no instrcutions or indications anywhere in the mobo manual for an 'ignorant' person like me to understand WHY?

Thanks Tweak'e. You've been so very much helpful.

ramu
09-07-2006, 09:27 AM
Hi ramu.

First of all (for your reading pleasure):
http://en.wikipedia.org/wiki/Front_side_bus

Secondly:
But can't we buy a mobo with the same FSB as CPU?

Yes, you can but motherboards that have the same FSB speed as the CPU, right now, most common Semprons are 533Mhz, AMD64 are 800Mhz and my new Fav is the AM2 AMD64 is 1000Mhz+ (1Ghz+) FSB.

Not sure if this helps but we did a job where we stuck a AMD BARTON CORE 2200+ into a 266Mhz FSB Motheboard (MAX), we had to set the FSB to 133Mhz even thought the motherboard could handle 266, because some CPU cores double the speed. I had a link explaining all of this, but I've lost it. It may have been because of the different Levels.....oh sorry, I dont remeber, it was a while back.

Thanks Vistra. Really helpful.

ramu
09-07-2006, 10:06 AM
Not sure but I think youre on drugs....first the semprons in the socket a range can only support 333 fsb.....ie 166 on clock frequency...the 754 semprons however have a 800mhz hypertransport and can support 400mhz ddr..the athlon64 in the 754 (which are not manufactured anymore) had 800 hypertransport and 400mhz ram ...ie 200 on clock.....the 939 athlon64 has 1000mhz hypertransport and can support 400mhz ddr the new am2 I believe still has 1000 hypertransport but can support up to ddr 2 800?? (I am not sure of that) and last but not least AMD NEVER MADE A BARTON CORE XP 2200+ the bartons started with the 2500+ or the XP-M series which started with a 2200 for mainstream and 2400 for the desktop replacements...a athlon xp 2200+ had to have been a thorton core or a thoroughbred core. and fore the recored if you set the cpu frequency to 133 that WOULD make the fsb 266 and would also set a 2200 at its correct speed of 1800 ....2200+ has a multiplier of 13.5 so 13.5*133= 1795.5Mhz and 133*2=266Mhz fsb does it not? So the moral of my story is I would never buy a computer from you!

Thanks Straitjacket.

Vistra
09-07-2006, 10:32 AM
first the semprons in the socket a range can only support 333 fsb.....ie 166 on clock frequency...the 754 semprons however have a 800mhz hypertransport and can support 400mhz ddr Yes you are right, it was a 333mhz, should of looked at the specs before posting. sorry. I was thinking of a Celeron while typing...sorry again.


the 939 athlon64 has 1000mhz hypertransport and can support 400mhz ddr the new am2 I believe still has 1000 hypertransport but can support up to ddr 2 800?? (I am not sure of that) and last but not least AMD NEVER MADE A BARTON CORE XP 2200+ the bartons started with the 2500+ or the XP-M series which started with a 2200 for mainstream and 2400 for the desktop replacements...a athlon xp 2200+ had to have been a thorton core or a thoroughbred core. Yea, your right, I've got the XP-M model. But I believe Ramu wanted to know about FSB, not what type of cores AMDs are. I was only giving brief examples from the top of my head.


and fore the recored if you set the cpu frequency to 133 that WOULD make the fsb 266 and would also set a 2200 at its correct speed of 1800 ....2200+ has a multiplier of 13.5 so 13.5*133= 1795.5Mhz and 133*2=266Mhz fsb does it not? That is what I said.


So the moral of my story is I would never buy a computer from you! Suite yourself

Either way, cheers Straitjacket

tweak'e
09-07-2006, 01:17 PM
sorry ramu, it was a long day. looks like jens link explains it all.

i forgot there is 266fsb with 133ram mobo's out there (ie non-DDR). i hope you didn't buy one.

yeah the 133=266 is a little confuseing, its as bad as intel 200=800 :(