Overclocking an AMD Athlon II x2 250 on an Asus M4A78LT-M LE?

[Jamie_Edwards]

Hi guys,

I've managed to overclock my cpu to roughly 3.6Ghz using the auto feature on the board.

Because I'm using the auto feature, I had a choice of a value between 200-550. I incremented the value up by 5 till I got to 260 and had a stable oc of just over 3.6Ghz.

But, when I changed it to a value of 265, it wouldn't post. So after I'd got it to post again with the default values I incremented up by to and amazingly I got it up to 262 with yet a stable oc. Then when I took it up to 263, it wouldn't post... again.

So I decided to have a go at the vcore voltage ( on my board it's called Over Voltage ) and changed the value of "auto" and incremented it up 0.625 ( as that was the default increment ).

Because I'm a complete beginner to oc'ing and read that if you pump to much voltage into the cpu, you could fry it, I took it up until 1.500v and still it wouldn't post and as I didn't want to fry it, I set it back to auto.

What I'd like to know is. Is that actually adding 1.500 volts on top of the current voltage ( which is around 1.488v )? Or is it starting from 1.500v?

I want to try and pull off at least 3.8Ghz and at it'd be amazing if I could pull off 4Ghz!

Could it also be that the board is throttling the oc to protect itself? Hence the constant no posting and "overclocking failed" message when I get it to post again?

 

[csf60]

The limiting factor here is your board. It is a lower end board and because of that it has trouble with an FSB higher than 260. No matter how many volts you give to your CPU, the problem is the mobo. Post here other voltages you can modify in BIOS to see if anyone would help here.

 

[Jamie_Edwards]

OK so as there's quite a bit of options here, I've copied everything on the page. Here's the options I have:

CPU Overclocking [Manual]
CPU/HT Reference Clock ( Mhz ) [250] // This equates to 3.5Ghz as this is the utmost stable clock at the moment.
GPU Overclock [Auto]
PCIE Overclock [Auto]

CPU Ratio and Voltage:
Processor Frequency Multiplier [Auto]
CPU/NB Frequency [Auto]
CPU Over Voltage [Auto]
VDDNB Over Voltage [Auto]
Load Line Calibration [Auto]

Hyper Transfer Configuration:
HT Link Speed [Auto]
HT Link Width [Auto]
HT Over Voltage [Auto]

Memory Timing And Voltage:
Memory Clock Mode [Auto]
DRAM Timing Mode [Auto]
Memory Over Voltage [Auto]

Chipset Voltage:
Chipset Over Voltage [Auto]

That's all the options I have :L

 

[jlan86]

I'm a little confused. I just got rid of this exact same processor (replaced it with an FX-4350) and I could have sworn the CPU stock multiplier was x15. It's 3.0 GHz stock, which means that turning up the base frequency 25% to 250 would give you 3.75 GHz. Is this the Black Edition? If so, do you have the multiplier turned down to x14?

Here's how I ran mine for almost 3 years: set base frequency to 250, set RAM to 1333 (1666 effective), set northbridge to x10 (2500 effective, and this syncs perfectly with the RAM running at 1666), and set CPU multiplier to x15 (3.75 effective). This was on a cheap ASRock motherboard with decent overclocking options, and on the stock AMD heatsink-fan and it still stayed around 45C even under heavy load. Basically, you're going about it the wrong way by hoping to get to 4 GHz by just increasing the base clock. Every time you increase the base clock you're increasing the CPU, the RAM, the northbridge and the HyperTransport and if any one of these things can't handle it your system becomes unstable and then you're left trying isolate which one, usually by turning down the multiplier on each one individually to see which one yields stability, or if that doesn't work, turning them all down to see if you can get any stability at the higher base clock and then turning them up one at a time from there. Once you do figure out which one is the culprit, you have to turn up the voltage for that component and see if you can get it stable. Increasing the CPU core voltage increases your CPU headroom (particularly your CPU's multiplier headroom), so if you increase the base clock and your RAM is actually the culprit, increasing CPU voltage isn't going to do anything.

For example, when I was testing mine, I tried taking it from 250 to 260 but I was not stable. This increased my RAM's effective speed from 1666 to 1733. Since the RAM was rated at 1600, I tried turning the RAM down from 1333 to 1066 so that after the 30% overclock it was running at 1386. The system became stable, which means my RAM was the culprit, but I wasn't happy with it running at 1386. So, I began increasing northbridge and RAM voltage to see if there was any way to get it to run stable at 1733. It couldn't do it, so I ended up turning my base clock back down to 250 and turning the RAM back up to 1666. I suggest you set everything to what I mentioned above and try to get that to run stable. If it's not stable, play around with the voltages on everything, not just the CPU voltage core. Once you get this setup stable, try increasing the CPU multiplier from x15 to x16 and bam, you've got yourself an even 4 GHz.

Good luck.

P.S.- I just realized I did not directly answer a couple of your questions. When you manually adjust the voltages, the voltage is listed is the actual voltage, not what you are adding to the stock voltage, so if you have it set to 1.5 volts, that means you are running 1.5 volts through your processor. Your computer not posting at all, in a weird way is your computer trying to protect itself. If it won't even post at 263, it's probably not really stable at 260 anyway. Remember that just being able to boot up is not enough to call it stable. I recommend running Prime95 and 3DMark 11 at the same time as a double-down stability test. If both can get through one full cycle while fighting each other for system resources, you're stable for sure. One more thing: if you went from stable to not even posting, it most likely is your RAM.

 

[Jamie_Edwards]

You're right about the system not being stable at 260. I started running mprime ( Linux's verison of Prime95 ) and about 30 mins in my system crashed. I turned it down to 250 and tried mprime again and had the system running full load with no errors and a temp of 49c for three and a half hours.

I'll have a go at what you said and get back to you.

 

[Jamie_Edwards]

Oh and I know it means nothing but my RAM is G.Skill Sniper Series RAM rated at about 1333 anyway... I think XD

 

[Jamie_Edwards]

Right, here's an update:

I've managed to change the following: and because I didn't quite know how to change the RAM settings I did my best:
CPU/HT Reference Clock [264]

Processor Frequency Multiplier [x14.0 2800Mhz]
CPU/NB Frequency [10.00x]

Memory Clock Mode [Manual]
MemClock Value [533 Mhz]

I cannot get a value higher than x14.00 with my CPU multiplier? Despite that, I've managed to get a higher CPU Ref Clock value of 264 rather than a 263 so it helped but the system wasn't stable enough and within minutes of starting mprime my system crashed.

While writing this I'm running mprime with the settings above but a CPU Ref Clock of 260 again to see if it's stable enough. My temps are running at roughly 59c :L

 

[jlan86]

Right, here's an update:

I've managed to change the following: and because I didn't quite know how to change the RAM settings I did my best:
CPU/HT Reference Clock [264]

Processor Frequency Multiplier [x14.0 2800Mhz]
CPU/NB Frequency [10.00x]

Memory Clock Mode [Manual]
MemClock Value [533 Mhz]

I cannot get a value higher than x14.00 with my CPU multiplier? Despite that, I've managed to get a higher CPU Ref Clock value of 264 rather than a 263 so it helped but the system wasn't stable enough and within minutes of starting mprime my system crashed.

While writing this I'm running mprime with the settings above but a CPU Ref Clock of 260 again to see if it's stable enough. My temps are running at roughly 59c :L

Unfortunately it looks like you have an Athlon II X2 240 with a locked multiplier, not a 250 Black Edition like I thought. That means you won't be able to do any multiplier overclocking. If I were you, I would just upgrade to a better AM3 processor. They're really cheap now. You could get this one for $55 http://www.newegg.com/Product/Product.aspx?Item=N82E16819103953 and it's basically the one you have now but set to an x17. Or maybe go with this http://www.newegg.com/Product/Product.aspx?Item=N82E16819103727. In the mean time, you can try to fry your current processor so you have an excuse to get a new one.

First thing I suggest is turn the reference clock back down to 250. Do you know what your RAM is rated at? If it's rated at 1333, you should leave that at 533 (2x533x1.25OC=1333) but if it's rated at 1600 you should turn that up to 667 (2x667x1.25OC=1666). If it's not stable at 1666 then you can turn it back down to 533 (1333) but if you do that then go ahead and change CPU/NB frequency from a 10x to an 8x. Running your RAM and NB at these lower multiples might give you some more headroom to run it stable at 260 since your CPU does not have an unlocked multiplier. Don't forget that you are probably going to have to manually adjust voltages if you want to get stable at a higher overclock. Alternatively, you may just want to leave it at 250 and be happy with your northbridge running at x10 and your RAM running at 1666MHz.

Just to be clear, the speed your BIOS seems to be listing for your RAM is half the speed before overclocking. So if you're at a 25% overclock, 533 x2 x1.25 = 1333MHz. Adjust accordingly.

 

[csf60]

Oh yeah, I took for granted you were downclocking the memory when overclocking the bus to 260. If you were not, your memory is the problem because it can't keep up that speeds.

 

[Jamie_Edwards]

As I live in the UK I'll probably go for this one:
http://www.amazon.co.uk/AMD-HDZ965FBGMBOX-Phenom-II-965/dp/B002SRQ214/ref=sr_1_1?ie=UTF8&qid=1372976414&sr=8-1&keywords=amd+phenom+ii+x4

Until then though, I might as well try and gain as much out of this one as I possibly can and try to get above my current stable 3.5Ghz.

My RAM is supposed to be rated at 1600Mhz @ 1.25v according to their website.

Just to recap ( as I've set everything to auto again ) I need to tweak the following?

CPU/HT Reference clock to 260,
CPU/NB Frequency to 10.00x,
MemClock value to the one next on the list to 533Mhz? ( I can't for the life of me remember what the value is )

And then start tweaking any voltages thereafter to try and get a stable 3.6Ghz?

If that's the case which voltages should I start with first?

CPU, HT or Memory?

Thanks.

 

[jlan86]

As I live in the UK I'll probably go for this one:
http://www.amazon.co.uk/AMD-HDZ965FBGMBOX-Phenom-II-965/dp/B002SRQ214/ref=sr_1_1?ie=UTF8&qid=1372976414&sr=8-1&keywords=amd+phenom+ii+x4

Until then though, I might as well try and gain as much out of this one as I possibly can and try to get above my current stable 3.5Ghz.

My RAM is supposed to be rated at 1600Mhz @ 1.25v according to their website.

Just to recap ( as I've set everything to auto again ) I need to tweak the following?

CPU/HT Reference clock to 260,
CPU/NB Frequency to 10.00x,
MemClock value to the one next on the list to 533Mhz? ( I can't for the life of me remember what the value is )

And then start tweaking any voltages thereafter to try and get a stable 3.6Ghz?

If that's the case which voltages should I start with first?

CPU, HT or Memory?

Thanks.

Well since you don't have an unlocked CPU, here's what I would do. Start from scratch and the the base clock back down to 200. We'll increase it again later, but for now we're just gonna play around with the other things. First of all, your RAM should be set to 800, not 533. Set it to 800 and set the NB multiplier to x12 (it should say 2400Mhz). Test for stability. If it's not stable, try increasing your CPU NB voltage. I can't tell you what to set it to, because it's different for all boards and CPUs. It should be set to a stock value, so if it's just barely unstable, turn it up one notch from that and retest for stability. If it's wildly unstable, try going up 2 or 3 notches to save time, but I recommend never going more than .21 volts over what it was initially set to. Even if more than that is not dangerous, if you increase it by that much and don't at least see signs of increasing stability, you're probably barking up the wrong tree and shouldn't be increasing it anyway. Feel free to push past +.21 if you feel like you're getting close to stability and all your temps look good.
Anyway, if you can't get it stable with the NB multiplier set to x12 even after increasing your voltages, then turn it back down to x10 and turn the RAM back down to 667 from 800. The only reason I recommend turning the RAM down in this case is because I find that I get the best performance when my RAM and NB are operating at a 2-3 ratio, so if you have to run your NB at x10, you might as well run your RAM at 667 to get more overclocking headroom. The inverse is also true. If I can't run my RAM past 533 I will turn the NB multiplier down to x8 to see if I can at least get more overclocking headroom with the NB turned down. If your NB is stable at x12, leave your RAM at 800. Leave HT at 2000Mhz and stock voltage for now.
Now you're going to start increasing your base clock. Even though you've already tested it up to 260, start by increasing it to 210. You're about to find out why. Test for stability. Move up another 10 if stable. Keep doing this until your start to see signs of instability. When it starts to get unstable, what speed is your RAM at? If you're unstable at just 210, your RAM would be running at 1680 and that could mean your RAM can't push much further than 1600. Try setting the RAM back to 667 so that after the 5% OC it's running at 1400. Is it stable now? If yes, you know that the RAM is what was causing the instability. If not, then it could be the northbridge causing instability. If it's the RAM, turn the RAM back up to 1680 (800x2x1.05) and start increasing the RAMs voltage to try to get it stable at 1680. If you can't get it stable at 1680, just turn it back down to 667 and let it go and change the NB multiplier back to x10.
If turning down the RAM does not improve stability, turn RAM back up and turn NB down to x10. Test for stability. If now stable at x10, turn NB back up to x12 and increase CPU NB voltage to try to get it stable at x12. If you can't get it stable at x12, turn it back down to x10 and let it go and change RAM back to 667.
If turning each one down individually did not improve stability, turn then each down to 667 and x10 and test again. Stable? If yes, then they both may have been bottlenecking at the same time. Turn them both back up to 800 and x12 and increase voltage on both. See if you can get them stable with both their voltages turned up. If you can't, then leave them at 667 and x10. If you can leave them at 800 and x12. If turning them both down did not improve stability, try increasing NB voltage (not CPU NB voltage mind you, but NB voltage). See if that will stabilize it. If it does, turn everything back up and continue.
You'll then increase base clock to 210 to 220 and do it all over again. You're going to do this until you can't increase it anymore, and from there you have to decide for yourself where the right balance is. Then when you're all done you'll try to increase hypertransport. When hypertransport becomes unstable you try increasing its voltage. And there's still more things like LLC, CPU VDDA, PCIE VDDA, and other things you can play around with.

If this all sounds overwhelming and complicated, it's because it is. It's why there is no end-all be-all guide to overclocking. It's why there are thousands of forum posts related to overclocking. There are no guides that can hold your hand every step of the way. You have to keep experimenting in the way I described above and get a feel for it yourself. Overclocking is a lot like feeling your way around a dark room. At first you're bumping into walls all clumsily trying to learn where everything is, but you explore until you get a visual of what the room is like in your head and you keep practicing until you have a feel for everything in the room and can move around it naturally. Every single set up is like a different room.