P5K-VM + E2160: I laughed, I cried, It moved me

Let me start off by saying my last serious overclocking excursion was with an AMD K6-2/500 and involved a lot of undocumented jumper settings on an Asus TX97-E, which turned out rather well given the rudimentary configuration options available at the time. So, when it came time to upgrade my system, I decided to pair up an Asus P5K-VM with an E2160, mostly because I needed some CPU power on the cheap to keep from bottlenecking an 8800 GT. That, and I would practically be guaranteed a massive overclock from the dirt cheap E2160. The P5K-VM is one of the top two recommended SFF OC boards. Note my easy use of the word guaranteed.

So, I brushed up my OC skillz - consumed the [H]ard C2D OC Guide and a bunch of other guides, read up on the OC characteristics of the P5K-VM and the E2160. I also picked up an OCZ DDR2 PC2-6400 Gold GX XTC Dual Channel kit (1GBx2). Given what I had read and the tools that were available to help, I had to laugh. This OC should be cake compared to the jumper shuffle from the days of yore.

After the parts arrived, I cobbled them together in an old X-QPack case with an Enermax Liberty 500W PS. I installed a Zalman CNPS7000B-AlCu cooler with an adapter plate, powered the critter up with stock settings, and got WinXP Pro installed. All was good. I then installed the latest versions of the usual OC tools (for me these were CPU-Z, CoreTemp, SpeedFan, and ORTHOS)

I started my overclocking adventure with the following BIOS settings:

C1E: Disabled
SpeeStep: Disabled
PCI Freq: 100
CPU Spread Spectrum: Disabled
PCIE Spread Spectrum: Disabled

These were not changed during testing.

I was going to list each different scenario I attempted during that first phase, but I'll save everyone the time and effort and just say that I couldn't set the FSB higher than 320 and pass the ORTHOS "Small FFT" test with anything but the following settings:

FSB Freq: 320
DRAM Timing: Auto
DRAM Freq: DDR2-667MHz
CPU Voltage: Auto
DRAM Voltage: 2.10V (this is actually the voltage recommended by OCZ for my particular kit)

Obviously not the stellar [H]ard OC I was looking for. I did dick around with the CPU Voltage, but it didn't do anything other than raise the core temps. I did notice the aptly named VDroop though, and that led me to consider and perform the VDroop mod for the P5K-VM. Cake mod, too. Weird thing though: before the mod the VDroop was 0.04V (i.e. the CPU Voltage would drop 0.04V under load); after the mod the CPU Voltage would bump up 0.008V under load. At any rate....

After the VDroop mod I managed to pass the ORTHOS "Small FFT" test with the following settings:

FSB Freq: 333
DRAM Timing: Auto
DRAM Freq: Auto
CPU Voltage: Auto
DRAM Voltage: 2.10V

Huzzah! 3.0 here I come. So then I tried the ORTHOS "Blend" test and....[Insert profane epithet here]! I cried....

Since it passed the "Small FFT" test (CPU stress) but failed the "Blend" test (stress CPU and RAM) I figured the problem lay with the memory-related settings. So, I tried the following BIOS settings in every possible combination:

DRAM Timing: Auto, Manual(5-5-5-15)
DRAM Freq: Auto, DDR2-667MHz, DDR2-800MHz
DRAM Voltage: 2.10V, Auto

No joy for any of them.

Somewhere during my movement between the keyboard and the fifth I keep in the cabinet, I recalled reading on some forum a guy got a E2160 stable using 375x8 instead of 333x9. On a lark, I went ahead and tried it using the following settings:

FSB Freq: 375
DRAM Timing: Auto
DRAM Freq: Auto
CPU Voltage: Auto
DRAM Voltage: 2.10V

This passed the "Small FFT" test with flying colors, and I had hope. BUT, it failed the "Blend" test around the 4.5 hour mark.

I'm not sure what to do here, guys, and would appreciate any input. I'm starting to feel like a blind man peeing all around a bathroom hoping to hear water splashing as some point. All inputs/comments/suggestions appreciated.

I've got that same motherboard and I have the FSB as 405. I have had it at that for 5 months 24/7 without a single problem. You already know your ram can do 400. Your CPU is limiting you most likely.

You will want to manually increase CPU voltage.

dat is roffle 4 me

I have the P5K-VM and have ran E2140, E6300, E7300 and a E8400 on it. E21XX chips are 200fsb chips and will not run 400Mhz fsb on P965 or G33 chipsets, but will on P35 or P45 from my experience. I have ran the E8400 past 4Ghz stable on this motherboard.

For your E2160, set CPU voltage to 1.35v, set front side bus at 333Mhz and run 3.0Ghz. You might be able to run lower than 1.35v download cpu-z and run that inside windows to read your core voltage. This motherboard has quite a bit of voltage droop under cpu load and that's what casues most of your Orthos crashes. I know from running the E2140 that Auto voltage was setting CPU voltage as low as 1.17v even OCed to 2.66Ghz, it was stable but to run3Ghz plus I had to go up on the voltage, I use that chip in a P5K (P35 chipset) running 400 x 8 = 3.2Ghz but it needs 1.35v. Never trust Auto voltage on an overclock. More Ghz means more voltage, even if you were to buy a real E6850 3Ghz chip it will not be running 1.17v for example. Most of these chips are 1.35v or 1.325v max and at the higher end of the speed bin it will need close to that voltage.

If you have 800Mhz DDR2 make sure you set memory voltage to what is required to run that speed. Very few meet JEDEC spec of 1.8v which is the default in the BIOS. Usually it will be on the memory label or you can look it up. I have some Corsair CAS 5 that are rated at 1.9v but do work at 1.8v I also have some CAS 4 that are rated at 2.1v.

You might want to look into a low profile cpu cooler if you don't like the temps. Zalman makes some nice 7700 series coolers for $40.
Jerry