Sony pcg-fx405 bios mod

by **max1971** » Fri Dec 16, 2005 7:19 pm

hello,

i've extracted the original bios of my pc a Sony laptop like in the subject (it's the european version of pcg-fxa36) in order to modify it to recognize new cpu and other. So i've opened it with Phoenix Bios editor but some items are read-only. How will I make in order to render them modificable?

Thanks

Max

by **max1971** » Sat Dec 17, 2005 2:06 pm

Please, help me

. i have to replace the cpu, an athlon 1 Ghz (100 mhz), with an athlon xp-m 1700+ (133 Mhz), but Sony has locked by bios the fsb at 100 Mhz

, so new cpu runs at 1050 mhz (100x10,5) instead of 1400 (133x10,5). If i use cpufsb i can't go over 115 Mhz fsb because bios doesn't change the divisor. This cause that pci bus go over 40 mhz and agp over 80 and system crash!!!! But the pll, an ICS 9248-168, can go up till 150 mhz, by the specs that i found in internet, with all correct divisors. So, i must mod the bios to unlock fsb setting that, i presume, are located in Phoenix Bios Editor ---> BCP---> System ---> Speed switching options and Speed configuration, but are read-only.
Can someone helps me?

Thank you very much :wink:

Max

PS: BIOS is a Phoenix v4 release 6 (Sony vers, R0121k5).

by **sunbirds** » Sun Dec 18, 2005 4:58 am

where is the bios download link ?

by **max1971** » Sun Dec 18, 2005 12:26 pm

You are right, sorry... :lol:

You can download from http://www.myplc.com/sony ---> bios

Thanks

by **max1971** » Wed Dec 21, 2005 10:59 pm

Hy,

even if none can help me :lol:

i've installed the new cpu but, like i said in the past mex, system recognize it like athlon xp 1100 instead of 1700+

because the fsb doesn't swithc to 133 mhz. I tried to analyze the bios with Phoenix Bios Editor but when i recompile all and try to reopen with this software i receive a message that some module is corrupted

. Why?
Where can i find some interesting and easy material to understand how does bios work? So i try to mod myself :cry:

Or, if don't ask too much, can some explain to me where i have to make the modification?

Thanks in advance and marry Cristmas

Max

by **max1971** » Wed Jan 25, 2006 8:36 pm

Hy to all,

even if none helps me

with phoenix bios editor, an hex editor and a little bit of fortune i've made some changes that i'll try soon, when will arrive to me a flash eeprom programmer :lol:

. Moreover, i've found some parameters that are very interesting...but i don't know what they means. In Phoenix Bios Editor --> Bios Configuration parameters ---> system i read two 'only-read' setting: Speed Switching option and Speed configuration. They are both disabled (00). First have three options : 1) controlled on pin 23 2) controlled on pin 24 3) fast speed polarity. Second have four options : 1) Controlled on CPU cache 2) controlled on External cache 3) controlled on chipset 4) controlled on other method.
Can, this time

, someone explaine if these setting are preplaces to regulate cpu and fsb speed?

Thank you very much in advance

Max

by **max1971** » Thu Feb 09, 2006 6:52 pm

Hy,

I'm still here....

How many possibility do i have to cook the BIOS if i flash it with one modified by Phoenix BIOS editor?

I'm asking that because i think i have found what blocks the mobo to switch to 133 MHz fsb and i would like to try.

Thanks in advance to all

Max

by **aerodigital** » Wed Oct 14, 2009 8:34 am

I have the EXACT same issue, I am trying to modify the "Speed switching options" and from what I understand they enable speedstep for a processor i purchases such as a pentium M dothan. I would also like to find out what causes bios editor to suggest its read only. can I hex edit the file and unlock the settings? If anyone has any more feedback on this it would be greatly appreciated.