need suggestion for overclocking

[soul786]

hi everyone, me new here

my specs
msi p7n platinum sli mobo (nvidia nforce 750i)
intel q9450 cpu
2x2GB ram ddr2 800mhz (new)
coolermaster haf 922 cabinet
neptwin cpu cooler
coolermaster 600w psu
2 nvidia graphic card, and 1 sound card (creative)

i m trying to overclock my sys
i want to keep my vcore at or below 1.360, so i set it there and found that i can go 1733mhz fsb with it (quad pumped) (433)
so,
fsb 1733mhz
vcore 1.352 (1.360)
vtt 1.300
nb 1.32
sb default, ram everything default
my cpu and ram freq r not linked i set them at manual, but it auto use a divider
so i manual set dram at 800,
and choose that cpu fsb which results in 800 dram adjusted freq
i mean at 1730fsb it adust 800 dram to near it but not 800 (automatically choose divider)
my temps monitored with hwmonitor, cores never reach 80c (77 or below)
testing softw linx and prime95
after 2hrs on linx on max stress (1846mb ram) bsod with 7f code
i also tested fsb 1745, vtt 250, nb 1.28, vcore 1.368, ram 800, everything else default, no error with linx for 3.5hrs, ran prime95 bsod with 7f after 13hrs (blend test)
it takes very long to get error and error is with bsod, sometimes 7f, and 1, 24 etc
mostly kernal mode trap
i think i should increase nb and vtt, but in my bios anything beyond 1.300 (vtt) and 1.32 (nb) is marked with red and caution "not recommended may cause unstablity"
system ok at everything stock
pls suggest

 

[redduc900]

Intel spec's absolute max. VTT at 1.45V for the Q9450, so try bumping it to 1.35-1.40V (may only require between 1.30 and 1.35V, so bump it up in small steps).

 

[soul786]

thanks for suggestion,
i will try it

 

[soul786]

hi,
increased vtt to 1.329
fsb 1733
running linx (problem size 15500, mem size 1846 MB) for 3hrs (110 times) now still running without errors.
temps each core below 80 c
mobo temp 45 c max
no errors so far
what is max safe temp for 750i (my mobo)?
and pls suggest how to minimize my time with prime95 to find stablility

 

[redduc900]

Since the processor is a 45nm, and Intel never published TjMax, it's assumed it's between 95 and 105C. So just keep distance to TjMax between 20 and 25C, and you shouldn't have a problem w/ the chip throttling. As far as Prime blend goes, try booting to Memtest86+ installed to a thumb drive to check the RAM for stability. If you get errors in Memtest, then we'll need to know the rated timings and voltage of the RAM at DDR2-800, including what they're set to currently.

 

[soul786]

i asked max safe temp for motherboard not cpu, but thanks for reply
as for ram, ram is very new, bought it sealed pack just 4 days ago.
ram is everything default. (volt 1.90, 800mhz, timing 6-6-6-18-24)

with 1733 fsb, vcore 1.352(1.360), vtt 1.329, nb 1.32, ram default 800mhz
i ran linx
for about 4hrs (150 times) no errors on max settings, then i left comp and came back, the screen was all black, no hdd light indication, clicked pressed buttons, but nothing, maybe a different kind of crash, with no message, restarted comp by pressing button.

i belive problem is with volt of vtt or nb, because if vcore is incorrect, error is very frequent and comes very fast with linx or sys does not boot.
here error comes after long testing.

i heard that some fft sizes can tell what is the cause of unstability(prime95)
like 20k for vcore, 512k for nb chipset etc.
plz put some light.
i m stuck