Here’s last year’s incoming freshman data for UC Berkeley. It does not differ significantly from UC Irvine: 46% Asian-Pacific Islander and 26% white with 4 % who refused to state a race/ethnicity. :
http://www.dailycal.org/2012/08/23/uc-berkeley-releases-2012-2013-data-for-entering-students/
They are all in the ballpark, but Berkeley/UCLA (the premium schools) are lower Asian and higher white than Irvine.
UC Merced is the sump school, with much higher Hispanic pop and much lower avg SAT scores then the rest. Several Cal State schools are more competitive.