Couple of NF7 v2.0 Questions

I recently upgraded from an Abit KX7-333 mobo to an Abit NF7 v2.0 mobo, and I have had a number of problems getting everything up and running. Some of the problems were my fault and some were related to my PS.

I finally have my 1700+ DLT3C JIUHB 0319 stable at 2.3 GHz (12.5*184) with 1.70 Vc. What I am confused about is the fact that this same CPU ran 2.4 GHz (12.5*192) on my KX7 mobo with the same Vcore. I have tried running at 2.4 GHz (12*200 and 13*184) with up to 1.75 Vc, but I cannot get it to be stable at either setting. Has anyone else seen this effect before? Where the same CPU needs more Vc to run the same speed on a different mobo. I am using all the same components with both mobo's (same CPU, heatsink, DDR RAM, etc).

My current setup:

NF7 v2.0 with 1700+ at 2.3 GHz with 1.70 Vc
512MB Geil PC3500 or 512MB Corsair XMS PC3000 (I have tried both) Cas 2.0 3-3-7 with 2.8 volts
SK-7 heatsink with TT SF II (with AS3)
GF4 MX440 video card (stock speed)
TT PurePower 420W PS (also tried Antec 350W PS)
20GB HD, CDROM, CDRW

I have also noticed that the NF7 reads 5-6C higher CPU temps than the KX7 at the same CPU speed.

Abit undervolts check the hardware doctor for the real voltage then up it in the bios until it matches in the reading. Temps are unreliable.

I had problems reaching 200+ FSB on the old bios, but now im on v 17 (you can dl it from the abit site - v 18 is buggy though) I have been able to go way past 200 MHz, that might be your problem, give it a go, you have nothing to lose

Yes, like Climbski said, the NF7 does appear to undervolt. A BIOS update could also be very helpful. Have you played around with all the usual BIOS settings (CPU Interface, Spread spectrum...)?

I think I have disabled pretty much everything in the BIOS (CPU interface, thermal throttling, Spread spectrum, APIC, etc.). Mine came with v1.7 of the BIOS from ExcaliberPC.

It sounds like I just need to increase the Vc some more, but I just did not expect that I would have to increase the Vc with this mobo. Although I guess it could be due to the mobo undervolting some.

CPU Interface should be enabled. I couldn't even boot above 2.35 or so without it. Bear in mind that the NF7 derives core voltage from the 12v rail, rather than the 5v rail used in most other motherboards. Perhaps your loading is getting slightly heavy. Increasing the Vcore should "force" it to stabilize a higher one.

Hey thanks Gautam. I enabled the CPU Interface, and I am now running stable at 2.4 GHz (13*184) with 1.75 Vcore. My load temps are 25C system and 46C CPU.

Regarding the 12V rail, I had to replace my Antec 350W PS with a ThermalTake 420W PS I had. The 12V rail was only averaging 11.73 volts with the Antec, while the TT PS is keeping the 12V rail at 11.86 volts.