If you can wait without causing yourself stress, might as well wait. The ram and a suitable motherboard seem likely to go on sale. Maybe a CPU. Unlikely for a video card in that class though.
Personally I would order them whenever you see a great deal on what you want to buy. I wouldn't wait until one specific day for sales on things that may or may not be on sale. There is no guarantee there will be a sale on that day for those specific parts in the brands you are looking for.
If you can wait without causing yourself stress, might as well wait. The ram and a suitable motherboard seem likely to go on sale. Maybe a CPU. Unlikely for a video card in that class though.