upgrade from i5 750 to i7 880 no improvement

[roudy-s]

hello i have a very strange problem i have upgraded my cpu from an i5 750 to an i7 880 in order to get more performance out of gaming but i see that the i5 750 was doing better job in gaming performance than the i7 880 it has like slow motion part of games and stuttering so what is the problem is my cpu i7 880 not working correctly or is damaged and how to check if it is damaged or not working correctly and thank you.

my specs are:
i7 880 not overclocked (and the i5 750 not overclocked)
16gb ram 1333 mhz
gtx 970 msi 4g gaming edition
2tb hard disk ahci

 

[imsqam]

First, I would not expect to see big differences in performance between the two CPU's. Here are the passmark scores of the 750 and 880 along with the i7-870.
https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i5-750+%40+2.67GHz&id=772
https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i7-880+%40+3.07GHz&id=833
https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i7-870+%40+2.93GHz&id=832

The single thread scores are pretty similar and this is the usual indicator of gaming performance. The 870 and 880 are almost identical. Looking at Tom's CPU Hierarchy table we see the 870 only one tier above the 750, not considered to be a significant difference.
http://www.tomshardware.com/reviews/cpu-hierarchy,4312.html

As to why the 880 stutters I did a comparison of the CPU features
http://www.cpu-world.com/Compare/333/Intel_Core_i5_i5-750_vs_Intel_Core_i7_i7-880.html

The only thing that I saw was that of course the i7 has hyperthreading but it had 64 entries for the Instruction TLB while the 750 had 128 entries. Not even sure if this would make a difference.
https://en.wikipedia.org/wiki/Translation_lookaside_buffer

To see if there might be an issue with the CPU you can try to run a Prime95 stress test to see if you have failures.
https://www.mersenne.org/download/