It claims it was merely attempting to avoid user faults.
Samsung has denied claims that it intentionally designed the Galaxy S4 chip to perform higher under tests than in real situations.
The mobile phone giant issued a statement after researchers showed the handset achieved a higher graphics processing clock speed when benchmarked by specialist software than when it ran more advanced games.
The company acknowledged the two situations created different scores, but Samsung said its aim had actually been to prevent users experiencing a fault.
The tests involved the Samsung-designed Exynos 5 Octa chip used in South Korean and other international versions of the handset. This chip, however, is not featured in the UK or US versions of the S4.
A contributer on online forum Beyond3D first raised the issue on Saturday. Luxembourg-based member Nebuchadnezzar said:
"Oh hell Samsung, shame on you! This GPU does not run 532MHz; that frequency level is solely reserved for Antutu and GLBenchmark."
This comment was in reference to the chip’s graphics processing unit, which was operating 11% faster when running Android and 3D graphics testing programs than what it would normally achieve.
Anandtech, a website reknowned for its chip tests, then backed up the claims. Two of its researchers replicated the tests and confirmed the higher frequency only became available when carrying out specific benchmarks designed to prove the S4’s processing power.
"This seems to be purely an optimisation to… deliver the highest possible GPU performance benchmarks," they wrote.
Samsung has strongly denied the claim.
"Under ordinary conditions, the Galaxy S4 has been designed to allow a maximum GPU frequency of 533MHz," it said. "However, the maximum GPU frequency is lowered to 480MHz for certain gaming apps that may cause an overload, when they are used for a prolonged period of time in full-screen mode."