Effect of OC on my mobo? for phenom 2?

[netxzero64]

I have a Gigabyte GA-78GM US2H mobo and a phenom II X4 920

I'm planning to go OC with this, my question is:

"is it safe to go OC on this setup/rig? even if I would just increase the FSB to its stable state without bumping on the voltages and I'll just by me a good aftermarket HSF to keep the temps at bay."

2nd: what will be the possible effects when I OC this with my current setup? and go using it for 20/7 well of course CnQ is on...

and your other advises will also be appreciated...

 

[Billb2]

If you just increase the FSB just a little w/o changing voltage, no extra cooling should be required.

But then why even bother with such a small improvement?

Learn to overclock and take advantage of the money you spent.

 

[netxzero64]

^ im just afraid to mess with the voltages so I just want to push it from 2.8ghz to 3.2ghz using stock voltage...

I'll buy an aftermarket cooler because my stock HSF can't handle the temps when I made it to 3.2ghz... it reached more than 60c when I run OCCT and that's quite hot for an AMD processor...

 

[imported_kiwik]

Check your mosfet temps or they'll blow up under load after a few months

 

[cusideabelincoln]

60C is not bad, really. And OCCT stresses the processor more than typical applications.


You should be pretty safe with the overclock you're looking to obtain. You won't be stressing your motherboard too much. The biggest thing you might worry about is cooling the VRMs, which are right next to the CPU socket. If you don't have a heatsink(s) for them, consider getting one. Or at the very least make sure you have good airflow in your case so that they stay cool. I don't think that motherboard puts heatsink on the VRMs, so you should probably look into it, although the board does claim to be able to handle 140W TDP. When you overclock, the processor will need more power, although it would use much more if you do increase the voltages.

 

[netxzero64]

what's mosfet? how can i check that? i'm only on stock clock now at 2.8ghz... because i'm still planning to buy an aftermarket HSF...

lets say i already have my HSF (deepcool ice blade pro DARK) and I've lowered the temps..

is it ok to stay with the OC settings using FSB to increase clocks without bumping on the voltages? and use my rig 20/7? what are the effects possibly when I do this? tnx

 

[netxzero64]

@cusideabelincoln

is there a hardware to cool the VRM caps for my mobo? i think not... but my case is antec 300 and system temps are cool...

or is it possible to check the VRMs temps?

 

[cusideabelincoln]

I'm pretty sure you can find VRM heatsinks. I'm not sure exactly where you can buy them, but maybe google would shed some light.

Although if you have really good airflow around the VRMs (CPU socket), I think you'll be OK with overclocking. That board supports the Phenom 9950, which is a 140W chip and does need more power than even a lightly overclocked Phenom II 920. Putting a heatsink on the VRMs is really just precautionary - never be too safe.

 

[Idontcare]

Originally posted by: netxzero64
I have a Gigabyte GA-78GM US2H mobo and a phenom II X4 920

The thing to be aware of and concerned about when overclocking AMD quads is whether or not the mobo was designed with the high-TDP (125W and 140W) quads or not.

Pop goes the MOSFET

The vast majority of the 780G boards have a three-phase or four-phase PWM circuitry design. These designs are completely acceptable for the 45W, 65W, 89W, and 95W TDP rated processors; however, drop in a 125W TDP processor such as the Phenom 9850e or 6400+ X2 and you are asking for trouble. Trouble is exactly we found, as each board we tested eventually succumbed to the greater power requirements of these 125W TDP processors.

What did we learn? Do not trust the product information and specification pages in the vast majority of cases. The CPU support pages tell the real story - some better than others, but in all cases the 125W TDP processors are not officially supported by current 780G motherboards (4/25/08 update - Finishing 100 hour test results with the 9850BE and three vendor qualified boards have passed to date with proper cooling of the PWM area). It just takes some effort to find that information (except for J&W) and this is something we do not think the user should have to do. In our opinion, the product pages lead the user down one path while the CPU support pages (which are sometimes difficult to find) tell another story. At this point, it pays to read the fine print or hope your favorite review site is able to provide this information.

http://www.anandtech.com/mb/showdoc.aspx?i=3279&p=2

If it was designed with those high-TDP quads in mind then the vrms are already outfitted to handle the amps without killing the board should you overclock a lower TDP processor to clockspeeds that require that kind of power-consumption.

I'm assuming your board is actually the GA-MA78GM-US2H, the next question is do you know if you have Rev 1.0 or Rev 2.0?

Regardless, both Rev 1.0's CPU compatibility list and Rev 2.0's CPU compatibility list distinctly omits listing compatibility for the 140W TDP quads.

They both have compatibility for the 125W quads though, so this means you should be able to push the OC's on your PhII quad quite a bit before you need worry about destroying your motherboard.

Going by this lostcircuits loaded power-consumption chart we see that a fully loaded X4 965 (3.4GHz) at stock volts (~1.4V) is pulling right around 95W (but remember the X4 965 is a 140W TDP rated CPU), so provided you keep your Vcore on your X4 920 below that of a stock X4 965 you should be able to safely overclock to at around 3.4GHz IMO.

 

[cusideabelincoln]

^The 140W Phenom X4 9950 is listed as supported, though. And even overclocked, his chip won't need as much power as the first 9950s. So accordingly he should be safe, although to be safer he could put heatsinks on the mosfets.

 

[Idontcare]

Originally posted by: cusideabelincoln
^The 140W Phenom X4 9950 is listed as supported, though. And even overclocked, his chip won't need as much power as the first 9950s. So accordingly he should be safe, although to be safer he could put heatsinks on the mosfets.

Hot damn, there it is 3rd down from the top of the list no less! Somehow my eyes glossed right over that when I scanned down the list.

So OP looks like you are good to go. More than likely your CPU will hit its overclocking limit before that board does. Putting heatsinks on your mosfets certainly won't hurt either, and it will add more lifetime to your mobo, but it may not be necessary with your board.

 

[drizek]

I have rev1.0 of that board and I can run my X3 720 at 3.5ghz at 1.4125.

I was able to clock it higher, up to 3.7 or 3.8 I think, but I did not want to raise my voltage to those levels. Stick to around 1.4v and you should be fine.

 

[Lemon law]

I note that netxzero64 placed an overclocking condition in saying, ""is it safe to go OC on this setup/rig? even if I would just increase the FSB to its stable state without bumping on the voltages and I'll just by me a good aftermarket HSF to keep the temps at bay."

And its not a bad way to approach the problem, but the cautious overclocker sneaks up on it. Assuming your multiplier is locked, the usual way is to increase the front side bus by some small increment, followed by a stress test of primes95 or similar, monitoring temperature all the way, and then checking to see the system will reboot. Plus an equivalent memtest86 to make sure memory gives no errors. If everything passes, raise front side bus again, and retest. Eventually you will hit a wall that varies even among the same processor where either vcore or ram voltage must increased or you get system instability. But as soon as Vcore is raised, cpu temps go up exponentially. And you can also try ram dividers and other tricks, but unless you really really need the speed, its probably best to stop at the point you need to raise vcore more than a tiny bit. And by the time you do all the testing, you almost wear your computer out.

Other people are more greedy, but its their money and their computer. I am still on the fence in terms of overclocking my e5200, but I am starting to play with it slowly. What is also attractive is that I have discovered I can slightly undervolt the processor and still get a small increase in front side bus.

 

[netxzero64]

@Idontcare

ok thanks bro... well i dont wanna go high on OC'ing my setup... just wanna go to 3.2 and that's fine with me... if my limit is a phenom 2 965 then I should say that I'm at a safe setup right?

and i don't want to mess with the voltages either because basically i don't know how to raise voltages and I don't want to risk my motherboard becasue I know that it could really affect my caps... and by the way my gigabyte GA-78GM-US2H is rev. 1... i bought this last may 2.... I have good circulation on my case (i think) =).

the sad thing only is that I don't think that I could find a VRM coolers here... =( and my planned HSF which is the deepcool ice blade pro is big (similar as dark knight thors hammer) and i dont think a VRM cooler can still fit...

@cusideablelincoln

I just hope i could find a mosfet cooler around here... well anyway thanks for the tips and advices... I appreciate all your tips and advices regarding my concern....

@drizek

good for your OC'ing because you have an unlocked multiplier so you can push it more =)

 

[Idontcare]

Originally posted by: netxzero64
just wanna go to 3.2 and that's fine with me... if my limit is a phenom 2 965 then I should say that I'm at a safe setup right?

No prob, and yep I think you are going to be just fine.

There is one caveat here though and that is if your particular motherboard happens to have a manufacturing weakness or flaw which would have resulted in the board dying sooner or later anyways then it is most assuredly going to die sooner under the added stress of overclocking (no matter how mild the OC) but not any sooner than it would have died (still prematurely though) had you popped a PhII 965 into the socket and ran it at stocks.

Just saying this could still kill your board if your board happens to have a predisposition towards an early death compared to the average lifetime of the same mobo without that predisposition.

 

[netxzero64]

@idontcare

then that's the risk i'm going to take... because phenom 9950 was able to fit in my motherboard then its just the same with the ph2 965 because of the 140w TDP...

 

[cusideabelincoln]

Just google "mosfet heatsinks" or "gigabyte vrm cooling" and you'll find a ton and variety of solutions to keep those mosfets cool. For instance you probably won't find one giant heatsink that will just fit on all the mosfets, but you can put smaller individial heatsinks on each board component.

 

[netxzero64]

@cusideabelincoln

does your board have a mosfet heatsink?