Both answers are wrong. The Celeron 420 will easily beat out an ancient pentium 4 ht at 2.8ghz. Its not even that close. Also the pentium 4 takes like 3-4x more electricity then the celeron. celeron scores 456 vs 336 of p4 at 2.8ghz.
http://www.cpubenchmark.net/cpu.php?cpu=Intel+Celeron+420+%40+1.60GHz
http://www.cpubenchmark.net/cpu.php?cpu=Intel+Pentium+4+2.80GHz
To put it into perspective an i7 3770k at 4.2ghz takes similar electricity under 100% cpu load to a pentium 4 2.8ghz ht and your 3770k is about 20x faster.
Heck 1.6ghz pentium m's released when p4s were around destroyed p4's at 1/4 of the power consumption.