Prescott 560 LGA775 & Asus P5AD2 - Acting funny

[eduncan911]

Ok, basics are in the sig. Temps are 'ok', but this cpu runs pretty hot anyhow. I dropped ~15C by switching to water cooling (max CPU temps are around 60C now @ stock).

Ok, using the latest and greatest Asus P5AD2 and latest bios that allows unlocking the LGA775.

From what i can find out, when unlocking this locks the multiplier at 14x (THG). Ok, fine. The FSB can be fully adjusted.

Setting it to 266mhz (266x14 = ~3.7Ghz) boots, but doing anything with the mouse or keyboard causes the screen to go black, pause for a few seconds, and come back. Right-clicking mouse, causes the same thing. Very annoying.

Ok, so I unlocked the PCI-E and PCI buses, setting them to 100mhz and 33mhz respectively (I think PCI Express is 100mhz, stock, right?).

No difference. So I set the memory to 400 and 533. Nada, same issue.

I can actually back the CPU back down to 2.8Ghz (14x200) and overclock the memory, pci-e, and pci!


So what's up here? Here's the article I'm trying to attempt (1066mhz FSB, 710mhz memory):

http://www.tomshardware.com/motherboard/20040916/index.html


Going to buy two more rads to attempt to bring down the temps. The Prescott 550 and 560s are rated at 115W heat output, where all other 478 Prescotts are like 77W. Major difference.

But still, the temps aren't that high to bump it a little more.


The Asus bios throws an Overclocking Failure warning too. Whenver I select ANY type of overclocking.

Is that because I am not using the mobo's CPU&HS connector?

Going to call Asus in the morning.

 

[eduncan911]

Something to think about as well, should I be messing with the voltages? I'm leaving set to "Auto", but not sure if I need to give it more. ANd if so, how much (the 560s are rated differently then the 478 chips).

Thanks!
-E

 

[nissmo300]

trying raising the voltage and see if it's stable, did you run prime?

EDIT: and by the way 60C at idle is pretty hot if you asked me

 

[eduncan911]

Yeah. 60C is very hot. But the 550s and 560s run much hotter then any other P4. Hoping other 550 or 560 owners would jump in here and let me know what temps they are seeing.

Figued out how to bump my memory to 600mhz (from 400mhz). System is acting nicely. I was able to get 3.8Ghz, but it locked up in a game... Argh. I'll try to raise the voltage a little.

Remember, the LGA775 have different voltage requirements then the older units. I'm looking for more informatiom from others on it.


"Prime"?

 

[MasterCraft]

Where did you get your SLI mods?

or are you jsut waitign for the SLI controller or something

 

[eduncan911]

Where did you get your SLI mods?

or are you jsut waitign for the SLI controller or something

Yes, I'm waiting on the mobos to come out early next year. I have two 6800 GTOs that are PCI-Express (which are clocked normally at Ultras, with the same memory. So call it a PCI-Express version of the Ultra). I'd love to take some measurements, if someone tells me how to compare with the AGP 6800 Ultra versions.

Thinking of water cooling it in the next few days after I get my other radiators.

 

[eduncan911]

trying raising the voltage and see if it's stable, did you run prime?

I bumped it from the stock 1.55V to 1.6V and it seems to be 'ok' at 4Ghz. Haven't done much testing on it yet. Not sure if bumping the memory to 600mhz before the FSB increased the cpu core voltage. Memory is now at 650mhz and voltage is set to auto.

The PCI-Express and PCI buses are set to auto as well at time being.

Idle CPU temps shot up from 42C to 63C though... Argh!


Need... more... cooling... Extra radiators will be here later in the week.

Ok, going to launch PCMark04 now @ 4Ghz. Any other good load-testers? I figured that, with M$ encoded loaded, should be adiquate to test 3D and CPU load (as well as the RAID0 36gb Raptors on a RAID controller card I'm using, with 256MB of cache ). Whoot!

 

[MasterCraft]

Yes, I'm waiting on the mobos to come out early next year. I have two 6800 GTOs that are PCI-Express (which are clocked normally at Ultras, with the same memory. So call it a PCI-Express version of the Ultra). I'd love to take some measurements, if someone tells me how to compare with the AGP 6800 Ultra versions.

Thinking of water cooling it in the next few days after I get my other radiators.

where did you get the ultras? I'm interested in getting one for myself, I just didnt realize they were available on PCI-E yet?

 

[eduncan911]

where did you get the ultras? I'm interested in getting one for myself, I just didnt realize they were available on PCI-E yet?

They aren't available retail.

The "GTO" is the Ultra in PCI-Express version. The "o" stands for OEM, only through places like Dell.

I picked mine from eBay for ~350ea. You can read the specs of the GTO on NVidia's site. SLI connectors and all.

 

[batboy]

The PCI-E lock don't work right, so for best results leavee that on auto.

Default vcore should be 1.4v or less, certainly not 1.55v like you said. I usually recommend not going above 1.5v for Prescotts.

 

[eduncan911]

The PCI-E lock don't work right, so for best results leavee that on auto.

Default vcore should be 1.4v or less, certainly not 1.55v like you said. I usually recommend not going above 1.5v for Prescotts.

So what cpu voltage do you recommend batboy? I see you are running an LGA775 as well at 3.9Ghz. I don't want to hurt anything, so I don't know how high I can go (or should go).

With everything "stock" at 3.6Ghz (and me bumping the memory to 600mhz), the voltages I am recording/seeing are:

CPU: 1.41
Memory: 1.8v
PCIE: 1.5v

When I play with (and don't like it) the NOS/Turbo feature, the voltage jumps to 1.55v for 4Ghz (888mhz FSB) when I leave the cpu voltage as "Auto". That isn't stable, but raising it to 1.60v makes it stable enough to use the OS and such.

I noticed the LGA775 spec from Intel now requires the CPU's HS and Fan to cool the surrounding components, especially the voltage regulators. Since I'm not running a heatsink and fan setup (water cooling), I wonder if that's my problem. The case does have excellent air flow (11 oem fans, sealed box, etc). But it may not be enough it seems.

I'll try to go back to the stock cooler and see.



Side note, PCMark04 locked the machine at about 5 minutes into the test for the 4Ghz @ 1.6v (wouldn't boot at 1.55v). It was nice while it lasted.

So you're scaring me about going to 1.65v.

 

[batboy]

I can do a stable 3.9 gig with 1.48v, 3.8 gig with 1.46v, and 3.6 gig with 1.42v. The default vcore on mine is 1.3675v or something like that. Read my Prescott cooling article listed in my signature. Even though it's for socket 478 Pressies, much of the ideas apply to LGA775 too. Like needing good case ventilation even with watercooling. You might consider making a side cover hole and mount a fan to intake fresh air towards the mosfets and northbridge.

 

[eduncan911]

You might consider making a side cover hole and mount a fan to intake fresh air towards the mosfets and northbridge.

I already do:



Two more fans in the front. The case is sealed up nicely as well.

 

[batboy]

Nice! What case is that? That's a lot of case ventilation. You should be fine. The i915/i925 chipsets will probably handle higher vcore then the i865/i875 mobos, but still, I would not recommend going above 1.55v (actual) even with watercooling and excellent case ventilation. What is the measured vcore under load?

 

[eduncan911]

Nice! What case is that? That's a lot of case ventilation. You should be fine.

ThermalTake Xaser III

http://www.newegg.com/app/viewproductdesc.asp?description=11-133-105&DEPA=0
^- gave u that link instead of companies cause the company doesn't have decent pics of it.

http://www.thermaltake.com/xaserCase/xaser3/v1000a.htm

The i915/i925 chipsets will probably handle higher vcore then the i865/i875 mobos, but still, I would not recommend going above 1.55v (actual) even with watercooling and excellent case ventilation. What is the measured vcore under load?

Maybe you have something here!

While watching the voltage, I run PCMark04 (everything stock). The voltage drops from 1.40v down to 1.32v!

Is that normal for the voltage to drop under 100% load?


While talking to Asus about another problem, he thinks there may be a problem with a grounding or pwoer-related (my SATA CD Rom drive disappears). It's a brand new OCZ 520W PS, other overclockers told me to get.

I'm new to overclocking.

 

[pwnt by pat]

Use a multimeter on the powersupply and voltage read points. Motherboard based voltage detectors are notoriously inaccurate.

 

[BigStan]

While watching the voltage, I run PCMark04 (everything stock). The voltage drops from 1.40v down to 1.32v!

Is that normal for the voltage to drop under 100% load?

Yes it is normal for the LGA775 proc voltage to be all over the map. Because if it's built in throttling, you will see voltage spikes and drops under load.

 

[batboy]

Bigstan is right. The Prescotts have what is called "dynamic VID" which automatically adjusts the vcore a little bit depending on power requirements. I don't know about that Asus mobo, but the socket 478 Asus mobos were notorious for overvolting at idle and drooping to the point of undervolting at load. My Abit mobo seems fairly consistent with vcore, but I have an Antec 550 True Power PSU. A wimpy power supply can cause flucuations too.

 

[woutertal]

Prescotts have a Vcore fluctuation allowance of 200mV. However, dynamic VID and the socalled 'loadline' specs cause droop. This droop is by design. The reason for this droop is the 200mV fluctuation allowance (from the loadline that is). In order to stay within that 200mV when the proc stops (causing a Vcore peak upwards), the powerplant runs at the lower limt of the loadline spec under load, and at the upper limit of the loadline spec when idling (to stay within the 200mV limit when the proc starts, causing a downward Vcore peak).

Hope you guys can follow me. To read up on the VRD (voltage regulator down) specs of the prescott, search the Intel site for a doc called: "VRD design guide". There is one for each socketspec.

Hope I didn't bore you guys

 

[mtb856]

eduncan, do you happen to have a multimeter to check the rails on the OCZ? One guy had a problem with one of the adjustable Pots being lower than it was supposed to be out of the factory.... if so, all you'd have to do is pop open the PSU and just adjust the Pots so your rails are apprx. like this.

+12V at 12.25 or so

+3.3V at 3.4V

+5V at 5.15V

I usually go a little over spec b/c the voltage drops on my Antec 550 when I'm running full load.

BTW, you can't necessarily go by the rails that BIOS reports... mine are off by .2V or more.