P4 Northwood 2.6GHz 1.42V 48°C Prime95 voltage stability issue?

[Ghetto_Child]

So I have a P4 Northwood 512K S478 2.6GHz 400MHz bus. Box says max voltage is 1.525V, I'm running Prime95 for a few hours now and my cpu gets up to 48°C and the voltage varies between 1.42V up to 1.44V when Prime95 is running. Rest of the time especially when idle the voltage stays between 1.48V-1.49V. I might have seen 1.5V but it doesn't stay there very long. This is all according to 2 different lavalys Everest versions looking at just the sensor section. Both versions show the exact same voltages in sync. The "overclock" section shows my cpu voltage is 1.45v and temperature there is 45°C. That section however is not updated in realtime. My cpu fan rpm in everest says between 4200rpm-4500rpm

So I'm wondering if I have any issues I should be worried about, is the voltage levels a problem or is it due to the cpu temp being so high?

[Ghetto_Child]

Wow still no one has an expert opinion.

[Amourek]

No, it has nothing to do with high temperatures. CPU voltage normally fluctuates slightly.

The voltage difference you are seeing when idle vs. load is called vDroop. It is common, affecting lot of motherboards and is not something to be concerned about... as long as the system is stable.

[Ghetto_Child]

Thanks for the helpful response Amourek. I'm glad my power supply has been stable for the last 6years being a Made in China and stock IBM NetVista system PSU.

On a side note what do you think of my cpu fan's RPMs and the 48°C cpu when at constant 100% load :?: The lowest temp I've seen the cpu at idle was 23°C.

[Ghetto_Child]

So it turns out I was having some instability but it doesn't seem any bit related to temperature. The PSU I originally had (7yrs old now) was either having unstable voltages or was just worn down too weak to support my hardware. My display was messing up that all the windows of my various programs would flicker between fully opaque and partial window transparency. You'd see pieces of windows of all the other programs at various places on the screen flickering rapidly between each other. This prevented you from knowing which program you were in and the only way to get rid of it was to guess at closing a few windows. Also if IE6 had any 1 process using more than 100MB of virtual memory that single process would crash.

It was very annoying but only occurred after running the system for several hours to more than 1day or if I opened a great deal of windows say 20xIE6 windows. Originally I thought it was the cause of playing with my virtual memory size, then I thought it might be the video card (flashed it with a modded bios years ago), then I thought maybe some ram was bad.

I changed the 7yr old AcBel 340W ATX PSU that came stock in my IBM NetVista A60 6838-C1U computer. I installed an Antec TruePower Trio 650W (courtesy of NCIX boxing week sale) and since Jan. 3rd have not turned off my PC and have been running Prime95. No more of that display issue. Now I just hope the original PSU was under powered and not faulty. I hope to use it for a less demanding set up or as a portable unit for testing other people's parts.

Now with the Antec TP3 been getting 50/51°C peak at constant 100% cpu load. I was originally thinking I should try get a better heatsink or better fan but reading online 50°C is fine for constant 100% cpu load?

[Ghetto_Child]

I managed to get my cpu temp to 41°C max during constant 100% load. Exactly where I wanted it to be and as a bonus it's even quieter than it was before. I have no clue which of these did the trick but I guess the PowerLeap PL-P4/N & Arctic Silver 5 combo is a far better cooling solution than I imagined. At least I won't be needing a better heatsink for this unit.

I made some changes inside my case. I cleared some wires away from the heatsink since they were blocking the exhaust comming off the PowerLeap heatsink fins. When the comp was running those PSU wires were very warm. Then I swapped my PowerLeap 70mm x 70mm x 15mm 5K RPM cpu fan with a ThermalTake 80mm x 80mm x 25mm 3K RPM standard case fan using a 60mm->80mm adaptor. The fan was making a lot of noise so I took this rare opportunity of me shutting down to replace it for cleaning. Turns out it's an Everflow brand hybrid sleeve & ball bearing model R127015DU, 4800RPM, 39.29CFM, 3.92mmH2O, 38.9dB(A).

Last thing I noticed was the heatsink had room to shift the sides up and down almost like it was balancing on a ball. I decided to apply some force evenly to ensure the heasink was against the cpu flushly. The "wobble" effect must be due to the PL-P4/N adaptor adding height to the whole heatsink/fan, cpu, adaptor combo over the socket.

It feels like a library in my home and that's with the case door removed. I can actually hear the hard drives clicking and spin once in a while and that's significantly louder than the rest of the comp. Now I just need to find a low profile 15mm version same size and get a fan grill to protect it.