Two remarks:
- Replacing a graphic card is easy. Replacing a CPU is somewhat more difficult. Moreover, you must be certain that your motherboard is compatible with the new CPU.
- Which of the two will have the most effect on the performance of your system depends on what tasks you run.
Kees
I'm looking to upgrade my graphics cards and processor. Currently I have a GTX 550 Ti and an i5 2400. The GTX 960 and i7-4820K seem to offer the best cost to performance ratio, so now I'm deciding which I should upgrade first? Which is going to make the biggest difference right off the bat?

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