How to enlarge SDRAM or NAND Flash of QQ2440V3

When I run WinCE 5.0 on QQ2440V3,I feel the machine a little slowly.
I want to know the frequency demanding of SDRAM,better give me some samples.^_^
Also I have look some information of NAND Flash on QQ2440V3,it is easier than SDRAM to be sellected.Waiting for your attentions and answers
Thanks..

HY57V121620(L)T is a 64MB SDRAM chip,if you have,you can have a try.

Mabey K9F1G08UOB-PCBO K9F1G08 NAND FLASH(128MB) is a better choice.