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Kuma 7750 BE

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jtschmitz

Registered
Joined
Mar 27, 2009
Hello World.

Hope this is in the right spot.

I'm brand spanking new to OCing (I've had nothing but a Toshiba Laptop for the past 3 years) and am having a ton of fun finding out my system's limits.

My Build:
Cheap Radimax Case
AMD Athlon 64 X2 7750 Kuma 2.7GHz Socket AM2+ 95W Dual-Core
Kingston HyperX 2GB 240-Pin DDR2 SDRAM DDR2 1066 (X4)
JetWay JHA07-ULTRA-LF AM2+/AM2 AMD 790GX
OCZ Stealth Extreme 700w PS
Cheapo 2600 ATI GFX

Stock system is 200 x 13.5 for 2700 GHz. CPU
5-5-5-15 @ 2.25 volts @ 1066 for ram.

Because i've been running the ram at 1066 the system is not entirely stable. I know some of you will hate this, but it ran smooth for an hour, so I left it as 200 x 14 for 2800 Ghz. 5-5-5-18 @ 2.25 volts @ 1066 for the ram.

If I take the cpu up to 15x (3Ghz) with no changes it BSOD's after 3 seconds of orthos (on the dot). If I drop the ram to 800 or 667 it still fails after 3 seconds.

My MB can take 235 bus speed at max, any higher and it wont post, literally at 240 it wont post.

I need help, I want to run at 3.0Ghz, maybe 3.2Ghz. I haven't touched voltages yet but i've been hesitant to do so. I spent some times last night and i'm currently running this fine. It made my 1 hour of orthos initial test:

cpu-z.jpg

Btw stock HT link is 1800 and ram is currently at 900Mhz (doh!) 5-6-6-18 in ganged mode.

I know Orthos needs to run longer, I also know that running 8gig's of ram on has been known to increase instability. Ram runs very hot, would I been fine droping the voltage down to 2.0 (ish) and of course fixing the timings?

Any help would be greatly appreciated. Also feel free to point out all the things I am doing wrong!
 
When you say that running your ram at 1066 it isn't fully stable, is the ram 800mhz oc'ed to 1066 settings? Or is it just 1066 that is unstable? As for the main issue, that is weird. You should be able to get atleast 3.2 out of a kuma before needing more volts. I can get 3ghz on my 5200+ by undervoltings.
 
enable ACC, set htt (bus) back to 200, 15X multi, keep volts below 1.5 (try 1.4 first) and watch your heat.

See thread 7750 lets see what happens.

Chance the ram is 1066 but the oc is with HT not multi.
Voltage (a small bump) can add stability.
Kuma is not the same as brizzy you must also power the L3 cache and every CPU is different also.
 
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its 1066 ram no OC I set it as thus in bios.

I'll check out the thread, I guess I should have looked their first.

thanks for the help i'll keep you posted.
 
EDIT: Forgot to add that ACC is on, but I just remember that a friend had me install amd's software clock calibration would there be a conflict or do they even do the same thing?
 
they do the same thing but no need to bother with software at this point just use bios.
 
:bang head

at 200x15..

Start voltage off at 1.35 manual set in bios (it was on auto, so 1.344 maxish under load down to 1.28 ish when not on load according to CPU-z). Boot'ed fine, past more than 3 second on orthos, but computer restarted no BSod just restart after 1-2 minutes. Tried 1.375 and then ultimately 1.4. At 1.375 it was ok but error just under 3 minutes, went to 1.4. Past 3 minutes fine on orthos at 1.4, but my core temp was reaching 55, and temp 1 on speed fan was at 70. Unfortunetly whatever reading that temp 1, is what the auto shut off is on my board so it shut down power. I did set the comp to shutdown if CPU reaches 70, but where is the temp being read, its not my core.

On a side note, at 1.375 according to CPU-z my voltage was at 1.425 under load and only 1.375 when not. Normal?
 
yeah stock cooling, at stock voltage my core doesnt go over 40 degrees, guess I need a better heatsink/fan combo any suggestions?
 
yeah I set the VDIMM down to 2.0 as it was running real hot, have not noticed any instability lately because of it.

Can't get this bad boy to 3.0 under 1.4v. 2.7-2.9 no problem, got from 2.9 to 3.0 and I get all kinds of problems.

My core voltage is set at 1.35 currently, according to CPU-z it is running up and down from 1.352 - 1.368 spends most of the time at 1.360 but only a couple seconds before it varies, ive seen it as high as 1.378. Is that normal?
 
If it's sitting at 0% idle it shouldn't vary much at all (±0.01v max). If you're running apps then that is very normal for virtually all boards. If the variance gets worse than ±0.02v then you've got real problems. Your numbers are near the edge but still within what I would call tolerable limits ... :)
 
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