Having a hard time getting past 200FSB with Phenom II 720 BE

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
my full rig is at http://30moons.com/pc_chiapet.php

The main rig:
AMD Phenom II X3 720 BE
Thermalright Ultra-120 Extreme/Panaflo 120mm FBA12G12L1A
Gigabyte GA-MA790XT-UD4P BIOS F5c
OCZ OCZ3P1600LVAM4GK (2GBx2) @ 1333MHz 6-6-6-24-5-30-10-5 1T
Hitachi Deskstar 7K1000 HDS721075KLA330, 750GB, 32MB Cache @ 7200RPM
4890 MSI R4890-T2D1G OC
Win XP Pro 32bit

I am totally stable at 3600 (200x18), 2600 NB, 2000 HT, 1333 Memory settings tight.

If I even try 220 with 1066 or even lower, I don't run stable in Prime95...I may hit 20 hours+ in one run, but in another it crashes earlier. If I increase CPU speed I crash faster, at 3700 I will get occasional BSOD's on boot.

I am trying to revisit the FSB to see if I can tweak it some more...maybe it's not even worth it given the above.

My benchmarks are:
3DMark06: 3DMarks: 16425, SM 2.0: 6760, SM 3.0: 7608, CPU: 4417
3DMark05: 3DMarks: 24200, CPUMarks: 16200
3DMark03: 60901

I may be a little limited by my older 750GB 7K1000 Deskstar.

Is it worth pursuing FSB at this point or just call it?
 
Dec 30, 2004
12,553
2
76
thanks to your 2600 cpu-NB speed (right?) you can disregard the FSB in peace.
Have you unlocked to a quad yet?
 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
thanks to your 2600 cpu-NB speed (right?) you can disregard the FSB in peace.
Have you unlocked to a quad yet?

Yeah I am at 2600 CPU-NB stable @ 3.6GHz.

quad unlock immediately causes a non-boot and forced CMOS reset. :( By the time software really scales to the 4th cores I will move on to the x6 or bulldozer more than likely.
 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
First link in the OP has my full rig and specs.

It's a 520W OCZ Modstream, vcore is at 1.5V (1.488 actual)...temps stay good. I have been running this at this speed since last June.
 

busydude

Diamond Member
Feb 5, 2010
8,793
5
76
First link in the OP has my full rig and specs.

It's a 520W OCZ Modstream, vcore is at 1.5V (1.488 actual)...temps stay good. I have been running this at this speed since last June.

Sorry, I missed that.

Anyway, I would be happy with this OC if I were you. vcore@1.5 is the limit, bumping the voltage any higher is not recommended.
 

BD231

Lifer
Feb 26, 2001
10,568
138
106
You're not going to get a C2 stepping chip stable over 200mhz cpu-nb in most case's.

You can however get your rig " 3D Stable " at around 240 to 250mhz CPU-Nb. By that I mean gaming/encoding will never load the bus to the point of failure like a stress test app would.

If you're a SETTI @ home type, leave the FSB alone. If you're a gamer, crank up the CPU northbridge and don't go past 1.3v nb / 1.50v core voltage. Core voltage can get to around 1.55v safely on some boards as tests show a lot of boards fall short on actual voltage supplied.

1.3v nb / 1.5v cpu will get you 240 to 250mhz northbridge @ 3.7ghz core max. With a VERY good x3 you're looking at 3800mhz max 3d stable overclock. 3500 to 3600 is your max prime stable on most any x3 though.
 

StrangerGuy

Diamond Member
May 9, 2004
8,443
124
106
An X3 720 @ 3.6 is pretty good OC. What is your current vcore? What PSU are you using?

If I were the OP i'll just leave the system as it is...It's not like he fine tuning the FSB upwards is going to make any noticeable performance increase.
 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
What's odd is if I set the FSB to 200 instead of 'AUTO' (which reports 200fsb) it will become unstable as well.

I am on the F5c BIOS and since they have had 3 revisions. I am going to try another one and see if I can tweak FSB.

According to this article the mainboard should be able to do better FSB, my RAM should definitely be able too.

http://www.xbitlabs.com/articles/mainboards/display/gigabyte-ma790xt-ud4p_8.html#sect0

I am wondering if I am tapping my power supply. It didn't work either with my 8800GTX though....I have a 28amp 12V rail.
 

DrMrLordX

Lifer
Apr 27, 2000
23,233
13,324
136
Have you tried raising your HT voltage yet? I've hit around 300-305 mhz HTT on C2 chips before. It can be done.

Also, a 28a 12v rail is uh . . . pretty weak, I'm sorry to say. That wouldn't explain why your system's stability goes to pot when you take the HTT off Auto, but it would explain why an 8800GTX and its peak power draw of ~170W (or more?) might cause your system problems. Your CPU is probably drawing over 100W all by itself.
 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
I have a 4890 now...I believe it should draw about 400W total with the CPU, hard drive, and my cd drives under load.

I am not sure on the real amps.
 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
Picked up a Corsair 750HX....60+amps now. Should be here Friday...I think my very occasional crash is probably due to my PSU being borderline esp with my overclocked CPU and GPU. I saw a 4870 and 3.7 Phenom pulled 404W on the article side of AT...my 4890 should be a tad less or equal power according to everything...however; since I am overclocking it may draw slightly more. I do have about 10 or 12 USB devices...not sure how much they suck down (phone charger x2, mouse, keyboard, cam, scanner, pda, tablet, colorimeter, printer, couple other things)...
 

heyheybooboo

Diamond Member
Jun 29, 2007
6,278
0
0
3600/2600 is pretty dang good.

You could try 15x11x240, and if it sticks try to work your way up to 250MHz before you would be pushing it with your RAMs (with the memory ratio at 533MHz). You could even drop the NB/IMC back to '10' to take off some of the pressure, there.

Does your BIOS have the 'save' feature for 8 overall configs? That's really handy. In my limited experience with GB mobos when using 'Auto' settings it seemed to me it tended to over-volt a bit.

Good luck!




--
 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
i did try to drop memory ratio and the NB first. Once the new PSU comes I will give it another shot.