Cannot Overclock/RUN 1T

[Shogo]

Hi, just built this pc for a friend, i wanted to have a small OC, stable.

Specs:

3800x2
Asus A8R-MVP crossfire 200
OCZ EL Gold GX XTC PC4000 2GB 3-4-3-8
raptor 75gb
Antec True Power 480
Ati X1900XT
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I manually set the ram timing to 3-4-3-8, but for the other timings such as TRRD and others, i left it on AUTO.

CPU is set to 250x8 1.35v. Ram is 1:1, but cannot boot in 1T, on 2T tought, system is 100% stable 16hr prime95 double instance + 3dmark 06 looping.

Tried 250x8 at 1.35v= Super stable, 160fps average on hl2 test, all max.
Tried 250x9 at 1.40v =2250, 173 average on hl2 test, failed prime after 5min
Tried 250x10 at 1.40v + vcore overvoltage enabled, 185fps average on hl2, failed prime in 2seconds.

stock ram voltage is 2.75, but option range for voltage is by 0.10 increments, so, 2.70 or 2.80, for all 3 test i tested it at 2.80

normally i shouldnt do any overvoltage to make the ram run at 1T....

what do oyu guys think?

 

[kdog]

I am noticing that this is not uncommon when running 2gigs.
Heavy 3d applications + 2gigs at 1t with high clockspeeds do not mix well.

 

[officermartinez]

Not sure if this helps.. These are my settings on my system. I have just a little higher than average overclock on my x2 3800+ but our systems are very comparible. I have 2gb's of PC4000 memory as well (3-4-3-8 @ 1T). Heck, you might be able to lower the FSB Bus Frequency to 240 and lower the CPU Vid Control to 1.375v. I had my system there for a few months at those settings and it performed just fine. That would be a solid 2.4ghz! By the way, nice system that you built for your friend!

MY CURRENT SETTINGS (Prime95 and Memtest'ed stable):

FSB Bus Frequency: 255
LDT/FSB Frequency Ratio: x3.0
LDT Bus Transfer Width: (down)16 (up)16
CPU/FSB Frequency Ratio: Auto
PCI eXpress Frequency: 100MHz
K8 Cool n Quiet Support: Disable
CPU Vid Startup Value: Startup
CPU Vid Control: 1.450v
CPU Vid Special Control: Above Vid 104%
LDT Voltage Control: 1.20v
Chipset Voltage Control: 1.50v
DRAM Voltage Control: 2.60v
DRAM+ .03v If it's not 3.2v: Disable