E8500 Overclocking

[pkilway]

So far got my new E8500 up to 375 x 9.5 = 3.56Ghz at auto voltage. Memory is currently running at 900mhz, 5-5-5-15 at 2.1v. As I up the fsb, I use a lower memory frequency (higher divider), so I know it can't be the memory holding me back at this point since I underclock it anywhere past this point.

 

I've tried upping the VID to 1.3, 1.35, 1.38, 1.4 but just can't get stable enough to load WinXP (it'll post fine).

 

At the current setting I was able to pass Linpack Testing at half memory for 20 passes, passed 16 (8 hours) passes of Memtest86 and temps run in 36C at idle and got up to 60C under load during Linpack testing.

 

After my experience with my E7200, I'm a little worried about the temps. I was eventually able to overclock my E7200 up to 340 x 9.5 = 3.23Ghz, with idle temps at under 30C and Load temps maxing at 48-50C. And to be honest, I kind of miss my E7200, I really haven't noticed any improvement in performance.

Edited June 11, 2009 by pkilway

[9KRacing]

Try adding some voltage to your NB. You probably will have to bump your NB to 1.3 and your SB to the same. I'm at 438x9.5 (4.16ghz) with 1.33 actual volts (1.31 in CPU-Z)... but it takes me 1.40 actual volts to go up to 4.2ghz. And I can't get any higher than that. These chips just start eating up voltage after a certain point.

 

If you can't boot into windows at 1.4 vcore at 3.5ghz then it's NOT your cpu voltage. Also I can run my chip at 1.4vcore and not overheat in Prime with a AC freezer 7 pro... I would think you can too. Hitting 70 degrees in prime under load for 15 mins is one thing, hitting high 60s under normal computing tasks is something else. Are you hitting the 60s with STOCK voltages? It kinda sounded that way from your post. Either way, that should be plenty of voltage to take you to 4ghz. Good luck man, keep us updated.

Edited June 11, 2009 by 9KRacing

[pkilway]

Are you hitting the 60s with STOCK voltages?

 

Yes, I am hitting 60C with stock voltage while running Linpack stressing testing (it's like Orthos/Prime95 but takes less time). Currently using an Acrtic Freezer 7 Pro, I've reset it twice thinking I wasn't getting a good contact with the ship, but temp are the same. Under normal usage the temp tops out around 53-55C.

[The Smith]

Yes, I am hitting 60C with stock voltage while running Linpack stressing testing (it's like Orthos/Prime95 but takes less time). Currently using an Acrtic Freezer 7 Pro, I've reset it twice thinking I wasn't getting a good contact with the ship, but temp are the same. Under normal usage the temp tops out around 53-55C.

Yeah that seems a bit high. I would verify the flatness of your CPU heatspreader and heatsink base.

 

BTW you can also try increasing the FSB voltage. What mobo do you have?

[Kingfisher]

If you ever have run the linpack tests you would know they creat a lot nore heat than prime 95 tests.

I wouldn't worry about your temps at all.

And just because someone gets a certain clock and a certain voltage means nothing.

There are no black and white overclock settings.

[pkilway]

My entire rig is in my signature, but my mobo is an MSI P43 Neo3-F (link is below).

 

King, very true. But I wanted to check here on the temps to make sure I wasn't going to burn my chip up.

 

Just looking for ideas to increase my overclock (would love to hit 4Ghz+). What are safe voltages for NB, VTT(?) and SB? And should I increase them all at once by a few tenths of a volt, or one at a time until it's stable.

Edited June 11, 2009 by pkilway

[MasterRy88]

Always raise them one at a time so that you know what the problem is. If you start raising everything at once you wont know what solved the problem and therfore wont be able to fix it in the future. Also by raising everything at once you run the risk of burning up something without even knowing it. Always better safe than sorry. As for you NB and SB voltages it depends on your MoBo, im not fimiliar with yours so I dont know just make sure your NB and SB dont get too hot and if they do maybe buy a cooler for them

[HD4850]

King, very true. But I wanted to check here on the temps to make sure I wasn't going to burn my chip up.

 

Just looking for ideas to increase my overclock (would love to hit 4Ghz+). What are safe voltages for NB, VTT(?) and SB? And should I increase them all at once by a few tenths of a volt, or one at a time until it's stable.

 

Your temps are fine. 60c with Linpack is not high at all... most ppl get 75-85c in Linpack

 

Keep your NB & VTT voltages under 1.4v

 

Don't worry about SB, since you probably won't be needing that. Not many ppl touch that

 

 

Right now, I suggest you raise your NB voltage a couple notches.

[Lackadaisical]

You stated that you are using a different memory divider when you try to go higher, so what is your memory actually running at when it fails? What do the rest of your ram settings look like, are they on auto? It might be that the motherboard is setting the auto functions differently when you are running the lower divider and those settings are causing problems even though the ram is running at a slower speed.

[shiver_8]

Don't even think about touching your southbridge. Your southbridge controls your graphics and sata it has nothing to do with your CPU, if you overvolt the SB you can fry parts! In fact the only thing I would touch is vcore, vdimm, nb voltage, cpu pll, and mch and cpu reference. I have my e8400 at 4.5ghz and i didn't need to increase the FSB at all, left it at the stock 1.2 volts. If you overclock properly you should not have to touch the VTT. FSB voltage increases allow the data going from the NB to the CPU to be "filtered" more so that it sends correct messages rather than incorrect messages which result in miscalculations and failures in stress tests. However, by carefully tweaking the NB voltage, the same result can be achieved without compromising the life of the cpu. Also as a trick make your mch and cpu ref voltages 61 to 63 % of your fsb voltages. If you tweak everything else right you can have an OC that uses close to stock voltages. Have fun!

[redj41]

I'm not super familiar with your mobo, but I was able to hit a very stable 4.25GhZ with my E8400 (almost the same CPU) on my 780i board. This is how:

I looked up the max voltage for the CPU on Intel's website, and adjusted mine to a few notches below that.

Then started raising my FSB until I wasn't stable.

I bumped FSB voltage a notch, and started again.

I adjusted my NB voltage as I was raising my FSB, sort of proportionally, but not at the same time. FSB up a few times, NB up a hair, FSB up a few more times, NB up a hair.

I did that until I couldn't get any higher.

I started dropping the CPU voltage until I wasn't stable.

Once I hit that point, I bumped my CPU voltage back up a little and haven't had a problem since.

 

It involves a lot of time and a lot of restarting and testing, but it works. I've used this method on a xfx 680i with an E6750 and an E6600, a xfx 780i with an E6750 and an E8400, A ECS P45 with an E8500, and a similair but modified version on an asus X58 with a 920.

 

I've kept my RAM at stock settings and voltage. I had some problems the first time around because the auto settings for my RAM were different than the manufacturers settings. Once I adjusted that I was good to go. I'd check your memory settings in the BIOS and make sure they are in accordance with the manufacturer's specs, and then maybe try this method of overclocking. As far as temperatures go, that can vary so much depending on your rig, your application of thermal grease, your heatsink, fan setup, ambient temp., etc. that it's hard for anyone to compare. I think the danger zone for these CPUs is around 75C, but you should check Intel's website for that. When I was stress testing (burnintest - 6hours, 3dmark, PCmark, extended Crysis playing, prime95) I never broke 55C, and usually hovered between 45-50C. I have a HAF932, a V8, a few extra fans, and a healthy dose of A5S on my CPU as well as the chipset heatsinks. With my AC on my living room is about 65F. If I turn the AC off and it gets up to 75-80F, I break 60C under load, and idle around 40-45C. Anyways, I started rambling. I don't know if it will help, but I found my max stable overclock by the method listed above.

[HD4850]

The problem here is, he's using a P43 chipset mobo. I think he needs to tweak his MCH reference to get past his "375fsb wall".

 

He haven't replied for a while, so I wonder if he still wants help or not..