why can't I overclock more than 3.1ghz

[Gaurav Duggal]

Yesterday I overclocked my computer from 2.8 ghz to 3.1 ghz. It was stable. I had an fsb speed of 222mhz(from default 200mhz with multiplier 14) but as soon as I went to 224mhz, the computer stopped responding. I used 'SetFSB' to overclock from windows.
I was monitoring the temperatures using speedfan and it never crossed 72c (this is the temperature I get in summers at 100% load). I also have a Cooler Master CPU cooler(I don't know which model).

processor PentiumD 820
mobo:ASUS P5LD2-VM
RAM:kingston value RAM DDR2 667mhz

 

[Cogman]

Overclocking from anywhere except for the bios is a bad idea. Really, from 2.8 to 3.1 on a pentium d (Prescott based?) is not a bad leap. To me, it looks like temp is what is keeping you down right now, so a new HSF should probably give you another 100-200 MHZ.

You might try lowering the Multiplier and raising the FSB to see if you can get higher that way. Honestly, though, Penitum Ds where not known for steler overclocks, I would be happy backing down to 3.0 GHZ, and seeing if I could lower the voltage at all.

 

[Gaurav Duggal]

Thanks for replying. Please note my PD820 is a smithfield. How do I lower the multiplier and the voltage.

Please note my P5LD2-VM is an older model having a bios from 2005, it doesn't have overclocking options(i tried updating the bios but it gives me some chip error).

I don't think temperatures are keeping me down as I have been running BOINC 24x7 for the past 1.5 yrs and in summers the temperatures are around 75-78c. Could it possibly be my RAM. In CPUZ I think it was running at 740mhz (from its rated 667mhz)?

Also I got a huge boost in performance @ 3.1ghz and am happy with it but would like to go to 3.2GHZ and more if possible!!!

 

[Cogman]

Humm, are you sure you have dug through all the options of your bios? Asus usually has fairly good overclocking options, of course not under that name... usually.

Anyways, Something else you might try is to check if speed step is enabled, if so, disable it. Also you want to disable the C1 state and virutualization stuff.

75-78 is REALLY high in my book, I have seen, almost consistently, instability start around 70C. 60C is about the maximum I like to see my CPU hit, especially when overclocking.

BTW, you are saying summer temperates are around 75-78c, are you talking about your processor temperature? Processor temperature is generally measured in Celsius (hence the C) and in the US we generally measure in the Fahrenheit scale. Water boils at 100C and freezes at 0C, it boils at 212F and freezes at 32F. So 20C is about 70F

The problem is possibly your ram, but most 667 ram will overclock to 800, I'm still holding my bets that it is the Temp that keeps you down the most.

 

[Gaurav Duggal]

I am sure it is 75 - 78c in summers (processor temperature according to speedfan). But that was at 100% load. I tried overclocking at idle (when temperatures were only 47c) still it got stuck at 224mhz FSB.

I called up ASUS technical support and they confirmed that the BIOS I had did not have any overclocking options. Also the BIOS chip couldn't be updated as the newer P5LD2-VM's (the ones having overclocking options in the BIOS) have different BIOS chips.

Do u know how much a new programmed BIOS chip would cost?
Sadly my pd820 doesn't have speedstep (I get a huge power bill),virtualization,etc.

Can we increase/decrease multiplier/voltage through a program in windows?

 

[OfficeLinebacker]

Could be a PSU thing. Those P-Ds suck power down like there's no tomorrow. What can your PSU provide on the 12V rail?

 

[Gaurav Duggal]

My PSU is a 300watt one so it must put something like 25amperes on 12 volts (not sure of this) provided the 3.3v and 5v rails are empty.
At 222mhz FSB it is stable in Orthos for around 12hrs (after which i closed it) but as soon as I turn it to 224mhz it immediately stops responding.

 

[brassbin]

I doubt a 300W power supply could have 25 Amps on its 12V rail, even if it has more than one 12V rail.

 

[Gaurav Duggal]

well I did a quick calculation
V.I = Power
12.I = 300watts
I = 25amps


EDIT: according to this I should get 25amps (I don't know if PSU's work this way).

 

[Cogman]

Originally posted by: Gaurav Duggal
I am sure it is 75 - 78c in summers (processor temperature according to speedfan). But that was at 100% load. I tried overclocking at idle (when temperatures were only 47c) still it got stuck at 224mhz FSB.

I called up ASUS technical support and they confirmed that the BIOS I had did not have any overclocking options. Also the BIOS chip couldn't be updated as the newer P5LD2-VM's (the ones having overclocking options in the BIOS) have different BIOS chips.

Do u know how much a new programmed BIOS chip would cost?
Sadly my pd820 doesn't have speedstep (I get a huge power bill),virtualization,etc.

Can we increase/decrease multiplier/voltage through a program in windows?

I wouldn't even want to try and increase/decrease the voltage through windows. Honestly, the system you are describing was not built for overclocking, and unless you are willing to pay the price, you are about at your peak.

47C Idle and 78C load is a huge delta, when you overclock that is only going to get bigger, as well, just as soon as you start overclocking the temperature will go up almost instantly. If you are starting at 47C I would say that you don't have a lot of headroom to go up. Not only that, but you are taking some serious risks of burning out your cpu. If you cpu hits 78C unoverclocked (as reported by speedfan) then overclocked it is going to push 80-90 That is VERY dangerous. CPUs will receive permanent damage at 90C, and then you will have to get a new computer.

Seriously, trust me that you have to get a new cooler, the one you have isn't cutting it. Also, a 300W power supply may be enough, but given you current setup I doubt it is a quality power supply (yes there is a difference between each 300W supply). You should consider getting a quality powersupply in the 400-500W range. I'm not an expert of PSUs, you'll have to ask another forum about that.

Thats all I can really give you, I think you have reached the limit of your current setup and unless you're willing to invest in better cooling (I STRONGLY recommend you do) a new motherboard, and a new PSU (and heck, by that point you might as well get a new CPU) then I would just be satisfied with what I have.

 

[Cogman]

One other thing that you are neglecting, the more you overclock, the more temp plays a role in how high you can overclock. Just because your cpu can run stable at 2.4GHZ and 72C doesn't mean that it can run stable at 3.0GHZ and 72C. Why do you think that people use (l) N2 to get their computers to uber high overclockes? The cores arn't going much above -100C and still they get much further then they would if they where at say -20C.

 

[jjmIII]

Your mobo and chip are maxed-out. I doubt your going any higher .

 

[PolymerTim]

Originally posted by: Gaurav Duggal
well I did a quick calculation
V.I = Power
12.I = 300watts
I = 25amps


EDIT: according to this I should get 25amps (I don't know if PSU's work this way).

Don't forget that the power is split over multiple rails and you don't get all 300W on just your 12V, even if you aren't using the 5V or 3.3V. Then consider that some older power supplies focused power on the 5V and 3.3V instead of the 12V until the ATX-12V became more popular. Then consider that some power supplies are built very cheaply and are lucky to give half their stated capacity. Considering all these things, it is not a good idea to judge much of anything from only the wattage of the PSU. You should at least know the specs on each rail, and ideally you also know from a professional review if the unit is capable of its stated specs. Even if the PSU can supply the power needed, the power might be very noisy when pushed to hard. Combine this with a cheaper motherboard with little voltage regulation and I think this is a primary cause of poor overclockability.

A few links for examples:

http://www.newegg.com/Product/...x?Item=N82E16817103428
An older style 300W PSU still for sale with only 13A on the 12V rail.

http://www.newegg.com/Product/...x?Item=N82E16817707050
and a noname brand that claims 22A on 2 12V rails

http://www.hardocp.com/article...Q2MCwsLGhlbnRodXNpYXN0
An excellent example of how some PSUs barely reach half their stated capacity. Note that this supplier actually sells some pretty decent PSUs, but they use at least 3 different manufacturers and at least one of them makes horrible PSUs, so you can't always even trust brand names (although some brands are more consistently good than others). For this reason, I will never buy another PSU again without reading a professinal review of it.

http://www.jonnyguru.com/modul...views&op=Story&reid=71
And my personal favorite is an example of just how ridiculous some manufacturers claims can be. Here, jonnyguru tested a handful of older PSUs collected from his readers in a contest. The first unit, claiming to be a 650W, failed on the first test at 184W. I guess the fact that you could buy it for $10 should have been a sign.

This has been a test of the buyer beware notification system, brought to you by a faithful reader of the Anandtech power supply forum. Have a nice day.

 

[brassbin]

^what he said

 

[taltamir]

Originally posted by: brassbin
^what he said

isn't the joke supposed to go something like "that's what she said"?

 

[Gaurav Duggal]

I'll just upgrade the BIOS chip (to get all the cool overclocking features), throw the Pentium D 820 in the trash, while replacing it with one of the E21x0 processors and then overclock it to around 3.0ghz.




Edit: forgot about the PSU. I'll just let this 300watt PSU remain in the rig (The pentium D 820 consumes around 130watt at load (stock 2.8ghz) while the E21x0 should consume lesser than or equal to this.

 

[toadeater]

Originally posted by: jjmIII
Your mobo and chip are maxed-out. I doubt your going any higher .

The mobo is maxed out, the chip isn't. Smithfields overclock pretty well on a good board. Not that it makes much of a difference anymore, since they're totally outclassed by any C2D.