P5B Deluxe hitting a wall at 459 FSB ...

Okay, so I've got the system in my sig assembled and now I'm seeing what it will do. I've got it up to 415x8 (3.32) at 1.375 vcore and I wanted to see what it would do if I dropped the multi to 7. I can get to 459x7 (3.213) at the same vcore but I can't get past that. At 460 it doesn't post. Nothing, nada. No beeps, nothing.

I think I've already eliminated the memory as I can run at 400x8 with a 4:5 divider at 4-4-4-10 timings. I've verified this with memtest86+. Well, at least I let it run for several hours with no errors. 9 passes, I think?

I've tried a lot of different voltages. Nothing seems to work. Here's what my BIOS looked like for the good OCs at both 7 & 8 multi:

AI Tuning ==================> Manual
CPU Frequency ==============> 415@8 & 459&7
DRAM Frequency =============> 830 & 918
PCI Express Frequency ========> 101
PCI Clock Synchronization Mode => 33.33 MHz
Spread Spectrum ============> Disabled
Memory Voltage =============> 2.3
CPU VCore Voltage ===========> 1.375 (1.4+ for the higher FSB)
FSB Termination Voltage =======> 1.40 (1.45 for the higher FSB)
NB VCore ==================> 1.45 (1.55 for the higher FSB)
SB Vcore (SATA, PCIE) ========> 1.60 (1.7 for the higher FSB)
ICH Chipset Voltage ==========> Auto (1.215 for the higher FSB)

CPU

Modify Ratio Support ==========> Enabled
Ratio CMOS Setting ===========> 8/7
C1E Support ================> Disabled
Max CPUID Value Limit =========> Disabled
Vanderpool Technology ========> Disabled
CPU TM function =============> Enabled
Execute Disable Bit ===========> Enabled
PECI ======================> Disabled

Advanced=>Northbridge Chipset Configuration

Memory Remap Feature =================> Disabled
Configure DRAM Timing by SPD ============> Disabled
DRAM CAS# Latency ============> 4 DRAM Clocks
DRAM RAS# to CAS# Delay =======> 4 DRAM Clocks
DRAM RAS Precharge ===========> 4 DRAM Clocks
DRAM RAS# Activate to Precha ====> 10 DRAM Clocks
DRAM Write Recovery Time =======> 4
DRAM TFRC ===================> 42
DRAM TRRD ===================> 10
Rank Write to Read Delay =========> 10
Read to Precharge Delay ==========> 10
Write to Precharge Delay =========> 10
Static Read C Disabled

Initiate Graphic Adapter =================> PEG/PCI


I didn't record the two? settings below this. I think one was PEG and it might have been disabled? In any case I left them at their default settings.

I also tried loosening the timings to 5-5-5-15 but that didn't help.

I also had problems at 420x8. Windows was extremely unstable. It kept dropping and rebooting. I really didn't play with the vcore to see if it would go higher. I just wanted to see if the CPU would pass the 3.213 mark I seem to be topping out at at 7 multi. I don't know if this is a valid assumption, but I am thinking if the CPU will do 3.32 @ 8 multi it should be able to produce a similar OC at 7 multi. I'm trying to isolate whether the wall is the CPU or MB. Is this a valid line of reasoning?

Anyway, I would appreciate any input. I guess I'm thinking the E6400 should go beyond where It's sticking and so should the MB.

By the way, at both the good OCs both cores were 51C - 53C (core temp) under dual Prime95 Small FFT torture tests for 3 hours with no errors.

The only other thing I can think of is maybe power issues? I am thinking I might try moving some fans off the MB headers. I have a YS-Tech 120mmX38mm 125 cfm fan in the CPU fan header, two Zalman 80mm 37.5 CFM fans, an OCZ memory cooler and a 40mm fan off a Swiftech NB cooler zip-tied to the NB sink and also running off MB fan headers.

I also have an array of other fans ... Two AC Ryan 77 cfm 120mm fans (blowhole and side panel feeding the YS-Tech), two 80mm Sunon 37 cfm fans in the side panel blowing on the video card and two Sunon 80mm 39 cfm fans for rear exhaust. Oh, plus a cold cathode line light running around my side panel window. I thought of disconnecting the cold cathode and three side panel fans.

So what do you think the limiting factor is? CPU, MB or PSU? Or my BIOS settings? Ah, one other thing ... I flashed from 507 to 910. Do I need to reinstall the drivers from my ASUS MB CD? Could that be causing any problems?

Update: It is some type of memory failure. When I reboot after a bad OC I do get beeps. One long and three short. According to BIOS Central that is:

1 long, 3 short Memory test failure A fault has been detected in memory above 64KB.

I guess I don't understand this. At 460x7 with a 1:1 divider that is DDR 920. I've passed Memtest86+ at DDR 1000 @ 4-4-4-10 & DDR 1100 @ 5-5-5-15. I"ve run 9 passes at both speeds with no errors.

Think it might be a DIMM slot? I installed the sticks in A2 & B2 just because of the spread on the SI-128. Of course the OCZ memory cooler looks like it will slide under the fins. Think moving the sticks to A1 & B1 would make a difference?

Oh, I also had to jack up FSB Term and NB voltage to get it to boot at 400x8 with a 4:5 divider. I also set ICH to 1.215.

Has anyone experienced this and what is the solution?

I think that board has a hole in the FSB somewhere. Skip up to 480 maybe?

Take a look at these threads and see if perhaps you've entered that "no man's land" with your Asus motherboard.

The use of other than default multiplier (7 in some of the examples above) can cause all sorts of issues with the Northbridge being overclocked more than what would normally be the case when using the default multi (8).

There is some interesting stuff on this topic (by the way, if you don't know, these guys are experienced overclockers).

http://www.thetechrepository.com/showthread.php?p=32#post32

http://www.bleedinedgesupport.com/ocz/forum/showthread.php?t=22297

http://www.xtremesystems.org/forums/showthread.php?t=114998

http://www.xtremesystems.org/forums/showthread.php?t=111400

Give this stuff a good read and see if maybe some of it applies to your situation.

Wow, thanks for that info Reefa. Some interesting reading! There's a lot to digest but I think I understand the gist of it. Sounds like the E6300 is the one that has the best chance of attaining a blazing FSB without overclocking the NB beyond its limits.

Hope that it leads to tangible results.

Let us know how it goes.

I've already got some decent results, I think? I have it Prime95 stable at 8x400 & 7x450. Now maybe I shouldn't exactly say Prime95 stable because I've only run it for several hours. When I settle on a good config I'll let it run for 12 or 24 hours. I still want to understand more about the strap changes and the effects on performance and how far I can penetrate into the 1333 strap.

You know I had read that one post by Tony a while back. That's why I was playing around with a 7 multiplier. And the followup post by freecableguy indicated the NBCC might handle as high as 571 (500*(8/7). Oh well, it looks like my P5B Deluxe maxes out at 524 (459*(8/7). Not really sure how stable that is but still not bad.

Okay, I gave up on the 7 multiplier. Best I can do and keep it stable for any length of time (3 hours Prime95) is 7x459. It just won't post above that, even with FSB Term, NB, SB & ICH maxed and more vcore than I could probably run (1.50) in any practical sense.

I have 400x8 Prime95 stable for 12 hours and 420x8 @ 1.4375v stable for 3 hours Prime95, though I am a little surprised at the jump in load temps. Up 9 degrees to 57C. Guess the SI-128 can't handle much more. I guess once the AS5 cures (I just remounted it yesterday) I might see a degree or two drop, but I don't expect much more.