I had an assessment day with Intel in November last year, so I am going to give you all insight to help you get though the AC.
There where about 10 of us, some travelled from countries around the EU. There was an icebreaker section upfront and we were told there was only 20 through to the assessment centre out a thousand application made.
The HR team gives you a presentation on Intel and then ask if you have any questions.
The first task was an in-tray exercise were asked to complete 2 tasks exercises, part 1 where you have to read and respond to the information presented to you and part 2 present your findings on an A1 paper. There was a lot of data so you have to move really swiftly.
Then you are asked to present your finding to 2 panel members, my panel members who are not so friendly. It felt like the interview in apprentice when Chris got grilled. The idea is not to panic and be confident.
After the in-tray exercise, you get a beak, this is when you get to meet graduate students on the same role, they are really friendly and seem to love their job.
After the break you, you have you 1:1 interview with two accessors. You get asked your typical competency based interview questions. The interview was 30 mins - an 1 hour long.
Last but not at all the least, the group exercise. This is very different compared to other assessment centres, it more interactive and fun. You are but into a group of 10 blind folded and given different shapes. Now the idea is to work out the missing shape. Its fun, just make you you speak up and contribute intelligently. I guess there are trying to work out your team working skills.
Well that was all, I hope this information helps.
PS Intel looks like a very good place to work, I was told by graduates working there they where given early responsibilities and the opportunity to come of with a product for their client.
All the best!