Many thanks guys, that was helpful.
Regarding the PSU though, taking GeForce GTX 950 as an example, the minimum power requirement is 350W. As I use my computer extensively for production of 3D graphics, what amount of power would you consider suitable?
My GTX 460 1GB RAM seems to be on the edge of dying if not dead already and I think of buying a new card.
I see used ones at around 50 pounds on ebay.co.uk
If I double the budget to 100 pounds what are the cards that are compatible with my Acer Aspire M7811 desktop and that you would recommend?
Just in cause, my PSU specs are:
Fsp Group FSP450-60EP
Max. Output Power: 450W - 500W Peak
AC Input : 100-127/220-240V 10/5A, 60/50Hz
Also, regarding my motherboard I can't find that many details.
There are two long numbers on a sticker, each starting with mbsdg0900
My processor is Intel Core i7 870

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