WTF?

[FZ1]

Here's a new one on me...
Yanked my CPU out (in sig) to test the new 170 I got. Finished and put the old one back in. Did a complete CMOS clear and turned her on. Entered all of my settings (below) that I had been using before that I knew to be stable (did not use CMOS reloaded). Will not load windows - gets to the "DMI" screen but never actually says it and hangs.

FSB - 317
LDT - x3
CPU/FSB Ratio - x9
Vcore - 1.450 x 110%
LDTv - 1.30
CHPv - 1.6
vDIMM - 2.6

DRAM Frequency Set - 166 (DRAM/FSB:5/06)
Command Per Clock (CPC) - Enable
CAS Latency Control (Tcl) - 3.0
RAS# to CAS# delay (Trcd) - 04 Bus Clocks
Min RAS# active time (Tras) - 08 Bus Clocks
Row precharge time (Trp) - 04 Bus Clocks
Row Cycle time (Trc) - 07 Bus Clocks
Row refresh cyc time (Trfc) - 14 Bus Clocks
Row to Row delay (Trrd) - 03 Bus Clocks
Write recovery time (Twr) - 02 Bus Clocks
Write to Read delay (Twtr) - 02 Bus Clocks
Read to Write delay (Trwt) - 03 Bus Clocks
Refresh Period (Tref) - 3120 Cycles
Write CAS Latency (Twcl) - 01
DRAM Bank Interleave - Enabled

DQS Skew Control - Auto
DQS Skew Value - 0
DRAM Drive Strength - Level 7
DRAM Data Drive Strength - Level 3
Max Async Latency - 8.0ns
DRAM Response Time - Normal
Read Preamble Time - 5.0ns
IdleCycle Limit - 256 Cycles
Dynamic Counter - Disable
R/W Queue Bypass - 16 x
Bypass Max - 07 x
32 Byte Granularity - Disable(8 Bursts)

So, I try 10 x 285 with the rest of the settings the same and it boots to windows, no problems. Now I'm confused.
> why can't I boot to windows @ 2853 (9x317) but can boot at 2850 (2850) when I was already stable at the 2853 for weeks?
> I changed absolutely no hardware except when I swapped CPU's
> My temps are great

I even tried using a bigger divider but it had no effect. Any ideas? It's killing me.
__________________

[infinitevalence]

I have had this before... no reall reason just some of the crazyness that comes with DFI. Your going to have to try your memory clocks as i think thast whats affecting your OC. My guess is a pin got some dirt or tarnish on it and that little difference is preventing you from posting.

[FZ1]

There is no issue with the memory - the OC is stable @ 10x285 but will not load windows at 9x317 - even if I throw a large divider on the memory.

Somethings up if I can run stable at 2850 on 10x multi but not on 9x when 9x was previously stable for weeks.

[kenc51]

try changing the LTD to 1.4v and up the chipset a little...
switch the ram around...

otherwise i haven't a clue...

[FZ1]

A few people have said it's my PSU. I have tested the rails at load, idle etc and they seem rock solid stable. However, when I was trying to prime the PC rebooted (on two occaisions) by itself. I wasn't watching it but I hear it restart so I'm not sure what cause it. Maybe the BSOD but I don't think I've ever seen one reboot. Then again, I don't wait around after one occurs either.

[FZ1]

Fixed. Re-flashed BIOS, did another CMOS reset and BAM! Back in biz.

[Apoptosis]

My OCZ Powerstream PSU's doesn't like the X1900 Crossfire and does give me BSOD's and reboots during benchmarks. Changing over to a new brand PSU is was fine.

New PSU's that are in the works have THREE 12V rails and over 48 combined Amps on the 12V rail.

The whole two rail sub 40A numbers we are all used to having is going to change real soon from a number of companies.

Good to hear the BIOS flash fixed the issue... Was it maybe a memory issue then?

[Bio-Hazard]

I've now got a simular problem, but mine is that I can't get my rig back to stock settings. As soon as I set it to default, I get a BSOD............... But I can re-set it to 250 HTT or above and all is well. I guess I could try reflashing the bios, might help.

Update:
The bios flash worked and all seems to be working right now.

[FZ1]

My OCZ Powerstream PSU's doesn't like the X1900 Crossfire and does give me BSOD's and reboots during benchmarks. Changing over to a new brand PSU is was fine.

New PSU's that are in the works have THREE 12V rails and over 48 combined Amps on the 12V rail.

The whole two rail sub 40A numbers we are all used to having is going to change real soon from a number of companies.

Good to hear the BIOS flash fixed the issue... Was it maybe a memory issue then?

Yep, I think it was a memory issue but teh BIOS re-flash helped as well. Here's the weird part. I still can't run at the timings I did before. I narrowed it down by booting all setting on auto and checking A64 tweaker to see what was autoset. I can run on all the same settings except:

Max Async Latency went from 8ns -10ns
Read Preamble went from 5.5ns - 6.5ns.

No matter what, I cannot lower these or it fails to boot to windows even though I ran them this way for weeks. Weird. Oh well, no biigie, I don't imagine that has a lot of real world difference in performance.