What is better for ue4, intel i5 or i7 why?

I want to buy a new computer, do i have to get one that has the intel i5 cpu or intel i7? who is better and why?
if i used i5 ,do i risk some bugs?

i7 > i5 generally, though you won’t have any bugs because of the CPU difference. You could happily use either, though generally, the i7 will be faster, so things like light baking will get done faster. Other features are generally more dependent on your video card than the CPU.

You just need to meet the requirements:

What are Unreal Engine 4’s system requirements?

For developing with UE4, we recommend a desktop PC with Windows 7 64-bit or a Mac with Mac OS X 10.9.2 or later, 8 GB RAM and a quad-core Intel or AMD processor, and a DX11 compatible video card. UE4 will run on desktops and laptops below these recommendations, but performance may be limited.

So, you need a quad-core, I would personally recommend you to compare models by looking at their performance in multiple benchmarks and pay special attention to cache size and effective clock frequency, this is what is going to make the difference.
But the most important of your new PC is that your components will work well together, have in mind you need 8GB of RAM, and the clock speed of the RAM is also something to consider (as well as if it is CL11, CL10…).
Good luck

NOTE: i7 > i5 is not a rule, so be careful and check model by model.

If your building from source I would recommend an i7. The hyperthreading will greatly decrease your compile times. I would also bump the RAM up to 16G, if you’re running a debug version of the editor and then debugging your game in the editor VS and the editor can easily use almost 8G of ram.

But if you’re just going to be using the launcher version it’s probably not such a big deal. Spending more money on a good video card might be a wiser investment.

If your looking to get a new CPU I would also wait a few months for Skylake. Even if you don’t pick up a new model the older ones will probably get a price drop.

Thank’s guys i appreciate it, I found a PC that i’m not sure if i have to buy it or not ,it got everything i need but i’m not sure about the RAM here is some infos about it:
Size:8 Go - 32 Go (maximum)
Speed:1600 MHz
DIMM 240 broches
And the GPU ,it has a 3 GB of memory, it’s a NVIDIA GeForce GTX 760

Do you know how many DIMMs the RAM has? If it’s 2 x 4GB with 2 spare slots then you can always upgrade later. If it’s 4 X 2GG or you only have two slots then you’ll have to replace all your ram if you want to upgrade.

I haven’t had a good look at the latest benchmarks but a GTX760 is kinda old tech now. A 970 is probably better value for money and has better power consumption. The 960 is supposed to be pretty good too if you don’t want to spend as much.

It has DIMM 240 pins what that means?
The pc is Asus PC Gamer G10AJ-FR027S any ideas?!!

Sorry all the info I can find on that one seems to be in french… I’m referring to the amount of physical sticks of RAM it has compared to the amount of slots for RAM on the motherboard.