Dothan 725 on T43

[Tekken]

I get spare part of Pentium M Dothan 725 400fsb instead 533fsb. Can T43 support this 725 cpu, if it can, will it run as motherboard 533fsb or 400fsb?

[emeraldgirl08]

I have the sister version of that laptop Tekken. I have the R52 which has a 750 Dothan so I'm guessing it should work.

[Tekken]

emeraldgirl08, does it run as 533fsb or 400fsb when you have 725 cpu on?

[emeraldgirl08]

Have a peek at this.

Proof.

Just had to show off my w7 screen also

Edit: I have a 750 Dothan on Tek. Sorry no 725.

[sktn77a]

It should work, but at 400/533*1600Mhz (ie 1.2 GHz). Not sure why you would want to do this.

[Tekken]

Dothan 725 has stock 100fsb. .Assuming it run stock 533 when I pop Dothan 725 in. 133fsb x 16 = 2.13ghz. Some cpu locked at 100fsb regardless what fsb running from motherboard.

[ajkula66]

It will NOT work right. Get a proper CPU, they are quite cheap nowadays...

750, 760, 770 or 780...

[Tekken]

Not work, why? please explain..

[Binh]

AFAIK, it will work but only at 100Mhz FSB.

However, you can easily do pinmod (or BSEL mod) it to get it work at 2.13Mhz. Search for information on Google.
Here is an example

[Terrahawk]

Hang on... the 725 chip is a 400 MHz FSB chip and it's going to go into a T43 that normally runs its CPU at 533 MHz FSB. What this tells me, is that the most likely thing to happen is that the 725 will do exactly as it is supposed to do, and run at 400 MHz FSB and 1.6 GHz. The worst that can happen is that the T43 is stuck at 533 MHz FSB and will run the 725 at 2.13 GHz. That may, or may not work.

[ajkula66]

If you get it to work, it will do so at lower speed and with stability issues.

T43s are moody enough machines without any end-user mods...

My $0.02 only...

[Tekken]

I agree with Binh... I think i need to do pinmod if i want to have it run at 2.13ghz

[Binh]

According to statistics, almost all of Pentium M 725 can work at 533 FSB (i.e. 2.13Mhz), most of them can even allow for undervolting.

For Tekken: Here is some information for you

and here

[emeraldgirl08]

Binh.

Thanks for those links. I learned something new today

@tek. Give us a follow-up if you attempt the pinmod.

[sktn77a]

It should work, but at 400/533*1600Mhz (ie 1.2 GHz). Not sure why you would want to do this.

Ah, sleep deprivation rules again! Of course, the 725 with a 400MHz FSB will want to signal the T43 to run at 400MHz, if the T43 can do this. If it can, your 725 would run at 1.6GHz. If it can't, it won't run at all. Apparently, there is a pin mod to get it to work at 533MHz (for a core speed ot 2.13) if the CPU can manage that. But both the T43 motherboard and the CPU will have to support and be stable at this FSB.

[Tekken]

Im sure T43 can support 533fsb.. Not sure if Dothan 725 can support 533 fsb on T43 default vcore 1.308v.. I want it run at default vcore to avoid heat issues.. If not, 0.016~0.128 voltage increase by pinmod to archieve 2.13ghz goal. Also tried to bid on ebay a 99 cent Dothan 1.7ghz 400fsb to archieve 2.26ghz. Anyway, will tried this 1.6ghz 400fsb first and let you know about heat and stable issue.

[Tekken]

2 Binh, can your 1.8gb boot in Window on default T42 voltage? How do you pinmod on increase voltage?

[Binh]

My PentiumM 745 1.8Ghz can boot into windows with default voltage, however it quickly fails on prime test so I have to voltmod it to get it stable.

So on my T42p using 855PM chipset, I pin mod the clock generator to force it work at 133Mhz FSB (or 533Mhz quad-pump speed) and voltmod the CPU to get it stable.

For your case with T43 (using 915PM chipset - aka Sonoma) and PentiumM 1.6, the only thing (probably) you need is BSEL mod, which means that you connect the "Bus-Select" BSEL[0] pin to low voltage in order to deceive the Sonoma chipset to think that you have put in 133Mhz CPU, but not 100Mhz CPU. Detailed information here

I think that in your case you do not need to make volt-mod since it is likely that the P-M 725 will work at 2.13Mhz with default voltage. If you are interested in volt-moding, you can read this or this

I do not recommend you to find PetiumM 745 1.8Ghz instead of P-M 725 since to overlock 1.8 chip to 2.4Ghz is not easy and may be unsuccessful. 2.4 Ghz comparing to 2.13 Ghz does not give much in increasing performance.

[Tekken]

Thz for good linky binh... I use to OC AMD in desktop and were spend most of time in OCforums. thz anyway.

[censored] I should get a 735 for 99 cent @ebay last time to get 2.26ghz.. Will let you know how this 725 go.

[Tekken]

I test out my Dothan 725 today.. When pop it in, it shows as 1.6ghz 400fsb. Pinmoded to connect pin 15th and 16th and it up 2.13ghz 533 on default voltage. Just supprise Dothan 400fsb defaut at 1.340 instead 1.308 as what my 1.86ghz does. Temp run 49c at idle and 57c loading, but my room temp 86F on 105F SoCal temp. I thinking to decrease vcore to 1.200 voltage to reduce cpu temp. what do you guys think?

I'll post some pics on cpuid

[Esben]

Thanks for the update, it's good to hear the CPU works well at 2.13 GHz. I'd recommend you try undervolting it with RMClock untill it gets unstable. My 1.7 GHz could go down to 1.036v, so I'd guess yours at 2.13 GHz could run at about 1.25v. Try experimenting a bit with different voltage levels. The only thing that can happen is your computer crashing, and then you just power it on/off.

[Tekken]

Im running under 0.700 voltage on idle and 1.248v @ 2.13ghz stable. Temp can keep under 53C during loading and 42C idle with room temp @ 78F.

I'm working on my 1.7ghz to 2.26ghz will update more info