Building Computer for Stats PhD student - what does it need



I have a relative who has a 6 year old computer that needs to be replaced. They will be starting their Stats PhD program and they said they plan on using SAS and R to do a lot of stats work. Are there any particular specs I should focus on?

My main question is the processor - are SAS and R benefitted from having multi-core processors, or should i just focus on the most Ghz. Also, any suggestions for the amount or ram?? Any other suggestions/tips are welcome!

Thanks for any advice you can share!!