script.bin/.fex, dram_clk and other properties

[dudo]

Hi.
My first question is which value is recomended (or default) for dram_clk property of script.bin file? I found in most script.bin files from olimex (e.g. in prebuilt image) value of 380 and in one file that I downloaded from olimex it was 408. If it's 380, shouldn't it be then 384 (16*24)?
I have A13-OLinuXinu board which is unstable on 408MHz, custom application is crashing and memory tester is reporting an error on memory test. When I set dram_clk to 384MHz, it's more stable, but it can still fail on memory test, but rearly. Other boards are ok with same software and memory tester.
And what if I set it to 360, is that ok if it's some lower value?
Another property or group of properties which are unknown to me are spi1_para properties.
Next is csi0_para. What does it mean when it is set to spc_used=1?

P.S.
I know for sunxi fex guide, but there is no detailed explanation.

Thanks.

[dudo]

Here is what I discovered about dram_clk (dram clock) property in script.bin. It's not used at all while booting A13-OLinuXino from SD card. Value defined in u-boot is used and dram_clk from script.bin is ignored. So, if anyone wants to change dram clock on A13-OLinuXino booting it from SD card, it should be done by editing file dram_a13_olinuxino.c and recompiling u-boot.