Overclocking Xeon 3210 overclocking limit, or user error!?

Okay, so after finding a special on a Xeon3210 (quad 2.13) from one of my suppliers, then discovering that my Zalman copper flower wasn't up to the task of cooling it and so got replaced with a Freezer 7 Pro, i decided to start overclocking.

I'm using the EVGA 650i Ultra motherboard that was reccomended by the staff at Bit-Tech as well as a few people i know.

I've had the chip stable at 3.2Ghz @ 1.41v for a few days. No issues, seemed stable, and temps kept under 60DegC.

I should probably explain i also have 2x1Gb sticks of OCZ Gold 667, and 2x 1Gb sticks of Kingston Value 667....and 800mhz 2.0v. No memory issues, no bsods, no erros in memtest (i do realise running unmatched sets is less than idea, but its all i had around, and considering i need the 4gb of ram...yea).

I've since pushed the cpu to 3.5ghz (437mhz fsb, 8x multiplier), and in the BIOS, i've set the voltage to 1.425v....

However, under load (the cpu does not rise above 70DegC), the machine BSODS.

I've noticed in CPU_z that the core voltage doesn't actually tally with what i set in the BIOS (yes im sure im setting the right thing), so am i just mistaken and in reality the setting in the bios is more of an "allocation" than a set rating?

The memory is still not causing errors, and it doesn't seem to be running too hot. Am i just trying to push the chip too far, or do i need to ramp up the voltage on the northbridge or something?

I'm confident on overclocking on the ole 939 platform, but the moment i moved to a core2 system, and i started being able to change things like the northbridge voltage....i'm starting to feel like im just barely keeping floating.

For the record though, if anyone here has an account with Northamber, i managed to pick up one of these for 100exVAT, and considering i moved from an E6400 that i used to run at 3.2....vista feels tenfold faster even when this chip was at stock!

 

Hang on: A Xeon won't fit in a normal LGA775 socket - they aren't pin compatible.

It's you're memory - at 800MHz you're running 1:1 at 400, so above that you're running faster again.

Check for vDroop on the CPU as well.

 

It looks like this one is. Its the same deal as the Opteron 1** series, where the server brand is applied to the desktop market. I believe the Xeon 3210 is essentially a rebadged Kentsfield.

 

Actually the Xeon X3210 is socket 775. What do you mean my vdroop? I've got the board set to -unlinked- so the memory is at 800 and the board is at 437mhz.

EDIT: Okay, i have no idea what vdroop is, however dropping the memory to 700mhz seems to have ironed out most of the bugs. I've just ordered some new 800mhz ddr2 from patriot, so that should make an interesting difference.

 

vdroop is the difference between the vcore you set in the bios and the vcore reading in, e.g. cpu-z. In other words, the cpu doesn't get the juice you think it's getting.

 

Ah ok, what setting would i have to alter in the BIOS to change this? I've hunted around in the voltage section of the BIOS, and all i can see are references to the memory, the cpu, the -cpu fsb-, northbridge and southbridge. Is there somewhere else i need to look?

Looks like the bios can't handle a 500mhz fsb, just attempted 7x500mhz fsb to give me 3.5, and it wouldn't post, even with 1.425v allocated. I've also set the ram back to stock to try to rule out any memory problems. 3.33ghz seems to work or 416mhz fsb at 1.425v. Temps still not increasing much over 60.