Decreased Performance after hardware upgrade

I am quite new to Percona/database servers and i dont know how to approach the following issue.

Couple of days ago i upgraded the hardware of a percona cluster (3 nodes) servers with a much more superior one.

Specs of prevous hardware:

Vendor: OEM
cpu: i7-3930K 3.2 GHz(12 cores)
RAM: 64G
I/O: software RAID

Specs of new hardware:

Vendor: DELL
cpu: Intel(R) Xeon(R) CPU E5-2630 2.4GHz (32 cores)
RAM: 128G
I/O: Hardware raid

The difference of the servers is huge and i was expecting that performance of percona(mysql) would significantly increase however after viewing various stats from new relic I noticed the opposite.

For example, some queries response time have increased from 2ms to 6ms.
Query time for some other select queries has raised from 50ms to 75ms.

Any ideas how to troubleshoot this?