downgrading fromm 533 to 400 fsb

[T400plus]

I want to try a 533 fsb based cpu onto a t41 motherboard.what will be the end result?
I have a T400 so please dont reply saying it is not the worth the trouble in terms of dollars(the us variety)

[RealBlackStuff]

If the CPUs are pin-compatible, it will probably work, but only at the speed of the T41 FSB (probably 400).
I'm not sure if that would be a stable solution.

[xob7]

It is pin-compatible, so don't afraid
But you have keep in mind that multiplier in CPU is locked.

Ex.:
Dothan M745 -> 1,8 GHz, bus 400 ( 4x100 ), multiplier x18
Dothan M750 -> 1,86 GHz, bus 533 ( 4x133 ), multiplier x14 -> on FSB 100: 14x100 => 1,4 GHz !

So if you put Dothan M7x0 it will work with lower speed.

You can try this: http://forum.thinkpads.com/viewtopic.php?f=2&t=52690

[sjthinkpader]

...I have a T400 so please dont reply saying it is ...

May you you can get an answer over at the T400 forum.

...... is not the worth the trouble in terms of dollars(the us variety)

I believe the comparative value of these parts are same everywhere, whether in US$, Euro, RMB or rupee. So if something is worthwhile to do in the US it would be probably worthwhile in China, India or elsewhere barring any border issues.

Other than Bill Morrow is based in the US, our members are resided WW so you will get a WW perspective on this forum.

[aaa]

I think he meant T40.

Before you even hit the mentioned multiplier issue (can't go more than 1.4ghz), the lack of BIOS support will cause it to be stuck at 600mhz.

There are ways to get around both issues, but the fsb issue in particular is not simple.

[T400plus]

thanks to all who replied and read the query.
Now i know how they get faster cpus from old cpu designs.They use better components and just soup up the multipliers ! +
change the system clock.
They do in hardware what that famous Bill used to do in new versions of windows to get upgrade dollars.

[sjthinkpader]

Boy, lots of side bar comments here.

Yes, that is the simplistic view. There are a host of supporting parts in a PC that has to go with a FSB change. DDR to DDR2 is a big change for that generation. They put the PATA back in the T43 in fear of poor SATA support by the way of a converter. Some call it the eco system.

Bill is not so bad if you consider driving different cars today. Each car has a different human interface. There are no standard in how things work. Some famous brand usability is so poor that one wonders how they made it into a commercial product and charge money for it. At least PCs are either Windows, Mac or Linux.

[Maccess]

I believe the comparative value of these parts are same everywhere, whether in US$, Euro, RMB or rupee. So if something is worthwhile to do in the US it would be probably worthwhile in China, India or elsewhere barring any border issues.

Other than Bill Morrow is based in the US, our members are resided WW so you will get a WW perspective on this forum.

Retail prices should be similar elsewhere, but for hacks, upgrades, etc. particularly of gear more than 2 years old it helps that your area has lots of sources of surplus parts, where you can get this stuff for cents on the dollar or even free.

[sjthinkpader]

Sure, but for comparing this upgrade us that upgrade, judgment point would be the same everywhere.