After Upgrading BIOS will not boot

[makapacs]

Hi,
I have Hp Pavillion 4540 with XP windows on it and i wanted to upgrade this system with 512k RAM stick, but it does not boot whenever i put 512K RAM in. So i figure that my bios has to be upgraded. I get the the Bios flash from HP website and flashed the bios. Now when i put 512K Ram stick in PC, it will not boot(similar as before i flash bios,only this time i can access to CMOS). I can access CMOS setting and there i can see that BIOS recognizes that in bang 2 there is 512k RAM but when i exit,than it do not go futher, stay there, does not load OS and display nothing, blank. After Flashing BIOS i did reset CMOS by taking out battery for 10 sec. When i put back previous RAM sticks that are 128 Mb than PC will boot and work fine.
Any ideas why it still not booting with 512k RAM after flashing bios?...The downloaded bios flash as discribed in Hp website would should take care of 512k RAM issues.

Thank's
Margots

 

[Cappy]

are you sure you have compatible memory for the board?

 

[makapacs]

Thank's MicroBell and Cappy,
I did not know that board is the one that determines the max size of RAM.(somehow Bios seem to be the god of gods). Could ever hapen to be that board are capible of biger RAM, but Bios not and on that case by flashing Bios,it will enable the system to take adventage of bigger RAM. Or whenever board is manufactured it is matched with the bios that already is compatible with the max RAM?...so by flashing BIOS it will never really allow to put bigger RAM.
I just flashed another Bios for another HP pavilion(6330) and it case, after flash it did boot with 512 RAM, but the OS showed only using 128 RAM. in this case is system using some part of 512 RAM or not? ..is it realy using only 128 RAM or all max 256, but only displaying 128?

MicroBell, i did flash BIOS with flcn_111.exe(link: http://h10025.www1.hp.com/ewfrf/wc/genericSoftwareDownloadIndex?lc=en&cc=us&softwareitem=pv456en) since my display adapter was not Sis 530 wiith version xxxx.1060. I have to admit before i flashed the BIOS, as it turns out now, i have not read discription of the flcn_111.exe very carefull and misunderstood it.
To sum up, there is no way to upgrade RAM higher than the board is compatible without upgrading the board?
Thank's
Margots