Fsb limit question for people with the PX845PEV Pro

[flxnimprtmscl]

Ok, so I finally got my new ram to replace the kingston value crap that was holding my oc back. But now I'm stuck again. I'm running at 180 fsb (3.42) with my 2.53 right now and I'm just not stable. Boot into windows fine but 3DMark2K1 and BF1942 crash to the desktop at random times. Things appear stable at 178 but I've only been playing with this for a few hours so I'm not completely sure.

Anyway, it's not my ram (HyperX PC3500) which is running at 360 because of the crappy mem dividers. I don't think it's my cpu because raising the vcore from the undervolted 1.5 actual to 1.525 actual got me jack in terms of stability. Not a temp problem because I've yet to see anything higher than 37C at full load. So my question is have I just topped this thing out fsb wise in which case I guess I have to go canterwood. Or is there a different bios (running stock one now) that might help me out a bit or anything else you might suggest? Thanks guys.

 

[SinfulWeeper]

Your memory should easily be able to handle 450ddr with 180fsb. My XMS 3000 is happy @ 425ddr running 2-3-2-7. (2.6 volts)

But I just posted in my thread about my suspect stability above 170fsb... only time will tell.

 

[Duvie]

First off it may need more then .025 vcore boost....


Second...I run at 175fsb at default vcore...I run at 180fsb w/ 1:1 ratio at 1.58v but needs 1.61v to run 450mhz ddr (highest I can go with my pc3000)...I run 183fsb w/ 1:1 ratio at 1.7v actual....

My suspect is the northbridge chipset....The temp issue could be there and I would suggest trying a cooling mod and slapping some as3 on it and a nice 40 mm fan...


I have no issues with memory dividers and this has been the best board I have used and running my Corsair pc3000...It would only do 426mhz ddr on my epox 4bda and 408mhz ddr on my epox 4g4a...The pe chipset seems to be the best I have dealt with in terms of memory and memory timings...

 

[flxnimprtmscl]

Originally posted by: SinfulWeeper
Your memory should easily be able to handle 450ddr with 180fsb. My XMS 3000 is happy @ 425ddr running 2-3-2-7. (2.6 volts)

But I just posted in my thread about my suspect stability above 170fsb... only time will tell.

No such luck for me. 450 was a no go even with 2.8v and 2.5 3 3 7 timings. I'll just have to see how a bit of burn in helps I guess. At the moment I'm pretty disapointed with these sticks though.

Thanks for the suggestions duvie. Time for a zalman and a fan I guess. Where do you find a 40mm fan at though? I've checked newegg and svc for one and came up with nothing.

Also what bios are both of you using? Do either of you know of one that's better in terms of stability than the one that comes with the board? Thanks.

 

[oldfart]

What HS/F are you running? What sensor are you getting that 37C from? That temp is way too low. If you are using MBM5, use WinBond 2 Diode and add 15C compensation.

As far as "crappy" dividers go, 4:5 and 3:4 are all you get on any 845PE. Is your PCIAGP locked? Try using the 1/5 divider instead. 180 would be 36/72. How high have you gone in Vcore? Try 1.575 - 1.625

Your CPU may just not do it. I see people griping that my CPU will ONLY go to 170 or 178 FSB instead of 185 @ default Vcore. Pretty spoiled we are. There is no guarantee. 3.38 GHz is not all that bad is it?

 

[flxnimprtmscl]

Lol, no, 3.38 isn't to shabby at all. I just thing there's more left in it

As far as my HSF I've got a Swiftech MCX4000 (lapped) with a very thin layer of AS3 and a Vantec Tornado. Not to mention very good case cooling in the form of 4 80mm Sunons. I don't doubt the accuracy of these readings at all. This setup kept my 1.6a @2.3 1.575 vcore at 22C idle and 29C or so at full load on a different board. Verified by the bios, mbm, and pc probe. On this board though I get the same temps in the bios as I do with mbm so I'm inclined to belive them.

And yes, my PCI/AGP is locked at 33/66 respectively. I'll try using the 1/5 divider when I get home tonight and see what I come up with.

 

[SinfulWeeper]

Guess we are getting spoiled :Q.
On mine, I removed that small NB heatsink and put on a much larger one and applied some ASIII. There is enough air flow in my computer that adding a 40mm fan would not help out a lot.

I was surprised at how small it was :Q. The last NB heatink I removed was for a KT133 chipset. This one was vastly smaller.

 

[oldfart]

Unless you are using WinBond 2 +15C, you dont have correct readings. I've messed around with this mobo enough to be sure of that. You have more than enough cooling, so temp is not your issue anyway.

You didn't say how much Vcore you tried. If you haven't already, try 1.575 - 1.625 range and see if you can get a bit more out of it.

 

[oldfart]

Originally posted by: SinfulWeeper
Guess we are getting spoiled :Q.
On mine, I removed that small NB heatsink and put on a much larger one and applied some ASIII. There is enough air flow in my computer that adding a 40mm fan would not help out a lot.

I was surprised at how small it was :Q. The last NB heatink I removed was for a KT133 chipset. This one was vastly smaller.

What heatsink did you use?

 

[flxnimprtmscl]

Originally posted by: oldfart
Unless you are using WinBond 2 +15C, you dont have correct readings. I've messed around with this mobo enough to be sure of that. You have more than enough cooling, so temp is not your issue anyway.

You didn't say how much Vcore you tried. If you haven't already, try 1.575 - 1.625 range and see if you can get a bit more out of it.

Great. I put sensor 2 on winbond diode 2 which reads at 10C. So according to you I'm running at a nice cool 25C at idle which is even better temps than I had before. Now do you belive me?

As far as vcore adjustment I've only went from 1.5 actual up to 1.525 actual. I figured another .025 would be enough to show some stability improvemnt since I'm only two fsb over stable. Maybe not though. I'll bump it up to 1.55 actual tonight and see what I come up with.

 

[oldfart]

25C? That is 77F Wow, that is cool. What is room temp? What is your load temp?

Yes, the extra Vcore can help. Dont be afraid to go up a little. I run 1.575 Bios which is ~ 1.54 actual. try that or 1.6, 1.625.

 

[Duvie]

Originally posted by: oldfart
25C? That is 77F Wow, that is cool. What is room temp? What is your load temp?

Yes, the extra Vcore can help. Dont be afraid to go up a little. I run 1.575 Bios which is ~ 1.54 actual. try that or 1.6, 1.625.

Hmmm...How come I undervolt more then you Oldfart??? I get .06-.07v undervolting as seen by MBM, Speedfan, and CPU_z (which by the way is the one I like to use)...

 

[oldfart]

Just checked it

Bios setting = 1.575

(Idle)
CPUz = 1.520 - 1.536
Speedfan = 1.52 - 1.55
MBM5 = 1.52 - 1.55

(Load)
CPUz = 1.488 - 1.520
Speedfan = 1.49 - 1.52
MBM5 = 1.47 - 1.52

 

[Duvie]

I get same load swings of .04 or less depending on app loading system but I am lower...I wonder if it is just the minor differences in boards, sensors, and/or power supply!!! hmmm...

 

[SinfulWeeper]

I dremeled a S370/A heatsink to size. Just a generic MWave one that I bought for my AMD tbird setup.
Getting the darned thing to mount while still retaining the stock mounting clips was a chore. It is on flush, but not square.

Anyway it stands about a ¼ or ½ a inch taller than the stock P4 heatsink w/o a fan.

 

[oldfart]

Originally posted by: Duvie
I get same load swings of .04 or less depending on app loading system but I am lower...I wonder if it is just the minor differences in boards, sensors, and/or power supply!!! hmmm...

Right now I'm on a generic 450 watt PC while I'm waiting for my RMA'd Antec True330 to come back. I dont think the readings were any different.

Originally posted by: SinfulWeeper
I dremeled a S370/A heatsink to size. Just a generic MWave one that I bought for my AMD tbird setup.
Getting the darned thing to mount while still retaining the stock mounting clips was a chore. It is on flush, but not square.

Anyway it stands about a ¼ or ½ a inch taller than the stock P4 heatsink w/o a fan.

I have a Zalman NB HS on order for the Abit IC7 I'm getting (must get rid of noisy NB fan). I also thought of using a socket 7 HS and still may. I'll see how it looks once it gets here.

 

[SinfulWeeper]

The Zalman is no all too big. Just a hair smaller than the stock IT7-Max2 MB heatsink. Then it was having difficulty mounting, but it finally did (I did not use the supplied glue, future options had to remain open).
Thats when it occured to me, why not just make a bigger one. With all the heatsinks I have around. I could make one better than the Zalmans. But I must admit though... I never once fired up the computer using the stock, or Zalman HS. Just the modified one.

 

[oldfart]

Its hard for me to say right now since I dont have the board yet. maxse tells me it will be difficult to mount unless I epoxy it. I'll scope it all out next week.

I know this much, I'm not going to let a NB fan ruin a quiet PC. This darn Radeon 9700P fan is driving me up the wall!! I'm getting the Zalman ZM80A-HP passive heatpipe to fix that problem.

 

[flxnimprtmscl]

Originally posted by: oldfart
25C? That is 77F Wow, that is cool. What is room temp? What is your load temp?

Yes, the extra Vcore can help. Dont be afraid to go up a little. I run 1.575 Bios which is ~ 1.54 actual. try that or 1.6, 1.625.

Today it was somewhere around a high 60ish ambient when I posted those temps. Right now with a 73 degree ambient I'm getting 28C @ idle and 36C @ load while running torture test.

I'm off to ratshack in a bit to pick up one of their crappy 40mm fans. I'll slap that and some AS3 on the stock NB sink (after I lap it of course ) and see what I come up with. If that doesn't help I'll try bumping the vcore up a bit more.

 

[flxnimprtmscl]

Well, it looks like duvie was right on the money. I wasn't able to get my hands on a 40mm fan but I did end up lapping the nb sink and slaping some AS3 on it. I'm now stable at 180 as far as I can tell without more testing. I'm actually kind of surprised. For one the NB core didn't look in good health after I got all the TIM off it (that stuff is the devil) plus the AS3 is still fresh. I almost was begining to wonder if I'd hurt things more than I helped by the time I got all that crap off the core. That stuff must be really God awful as far as heat transfer.

 

[Duvie]

Originally posted by: flxnimprtmscl
Well, it looks like duvie was right on the money. I wasn't able to get my hands on a 40mm fan but I did end up lapping the nb sink and slaping some AS3 on it. I'm now stable at 180 as far as I can tell without more testing. I'm actually kind of surprised. For one the NB core didn't look in good health after I got all the TIM off it (that stuff is the devil) plus the AS3 is still fresh. I almost was begining to wonder if I'd hurt things more than I helped by the time I got all that crap off the core. That stuff must be really God awful as far as heat transfer.

Hmm...maybe I should take my own advice!!! Let me know what your sys temps look like now!!! I can get high 38-39c according to speedfan...I have suspected that in my own case as an issue in stability at higher fsb....

Keep us informed after you really stress it...

 

[flxnimprtmscl]

Sorry, should have posted temps when I made my last post. Anyway, NB temp is now at 33C at the moment according to mbm. It was right around 37-38 before so I'm guessing you could gain quite a bit from a little AS3 and a fan. I realized a bit ago that the NB is right in the path of one of my 80mm case fans so I don't think I'd gain too much by adding one on the sink iteslf. I'm looking at these temps from the perspective that all I did was add the AS3 since I pretty much figure the way I roughed up the core negated my lapping the sink. Oh well

Right now FSB is at 182 @ 1.55 actual which seems to be the sweet spot for me. I booted into windows just fine as high as 185 (highest I tried) but it wasn't about to be stable while stressed no matter how much juice I fed it. So close to a 1Ghz oc So, ruling out the NB temps (since they're still lower then before) I figure I've either just maxed out the chip or finally come up against the board. Oh well, can't be displeased with where I ended up. Much thanks though for the extra 4 FSB since I was to retarded to think of NB temps on my own :beer:

Edited because I'd listed the wrong damn temps

 

[oldfart]

I'm a quiet PC guy, so you will never see me adding a NB fan (I remove them), but I always remove the NB and put some ASII on it as standard practice.

Glad to see you have it running well.