5th dragoon guards April 1904 - December 1908 - by: Susan Smith

I know that by 1904 the Anglo Boer war was over, but I wondering if anyone could point me in the direction of discovering what the 5th Dragoon Guards were doing between April 1904 and December 1908 - My grandfather's service record shows that he was in South Africa between these dates but I've been unable to discover any details. I know he was in Bloemfontein in December 1905 as the family has a Christmas card from there at that date.
Where can I look? Thanks in advance!