(1) RAM type sis630 IPL.S read is not 04

I debug sis630 IPL.S, I find the RAM type value that IPL read is 01 or 00 for different RAM but not 04. But my RAM is definitely SDRAM. The code is:

...........

movb $0x02, %al # Read the RAM Type (SPD byte 2)
CALL_SP(read_spd) # of the dram on current DIMM.
movb %bl, %al # %bl is 01 or 00 for different RAM,not 04

outb %al, $0x80
cmpb $0x04, %bl # If the RAM Type = SDRAM ??
jne no_sdram # no, exit

.......

Is there any bug in the codes reading spd bytes?

(2) for some Sis630 mainboard, docipl will hang. Linuxbios can't be executed. I think the RAM initialization procedure is as compatible as BIOS.

Thanks

zhu