Intel Burn Test Slower with XMP

[jlwmanagement]

I recently got a new mobo: MSI Z77A-GD65 and i easily got my 2500-k to 4.5Gz. The problem is that I initially left XMP off for stability testing and was getting 104 GFlops. I then enabled XMP and was getting 96-98 GFlops. I never got a crash and am stable with Prime either way. I was just wondering why would I see such a result?

Any ideas?

Thanks in advance!

 

[redduc900]

What model of RAM do you have, including the rated frequency, timings, and voltage? Assuming you initially left the DRAM frequency and all the timings on Auto, what were the before and after settings when having XMP disabled and enabled.

 

[jlwmanagement]

G Skill RipJaws 4GB DDR3 RAM
1333 7-7-7-21 1.5v

The only thing that changes is the voltage goes from auto to 1.5 and the timings go from 9-9-9-24 to 7-7-7-21
The frequency is always 1333. At least that is all I have seen change

 

[Bobnova]

The numbers IBT cranks out are amusing. I recommend ignoring them completely.

 

[jlwmanagement]

Thank you for your input.

Why would you say that? Even if they arent exact, wouldnt it be important that they are relative to one another? How much higher isnt as important as the fact that it is higher. Additionally, if not IBT, what would you recommend for standard benching?

 

[ssjwizard]

To measure CPU performance you want to look for some long running multithreaded benches. wPrime1024M set to max threads is a decent measure though not terribly ram dependent. Cinebench is another good one. UC bench set to run all tests is definitely long enough to measure even small differences.

 

[Bobnova]

IBT responds to things very strangely. More computational power doesn't always equal higher numbers.
The best example is HyperThreading, which typically improves performance by 20-30%. In IBT it lowers the score.

 

[jlwmanagement]

If anyone is interested in the solution, I raised the VCCIO to 1.1V and it works fine now with XMP on. Weird how I would have to increase that for something that is natively "supported" by the board.