Load causes fan sound to change pitch.

[GotNoRice]

I built my old Xeon rig back in 2003, and I went with an EPS12V powersupply because back then they were the only ones that had 24+8 connectors. I recently upgraded to an overclocked Q6600 rig but kept my old powersupply. It seemed to me like it should be enough, since it had many of the same features of modern supplies (24-pin, dual 12v rails, etc).

http://www.fsp-group.com/english/1_product/2_detail.asp?mainid=2&fid=54&proid=33

Other than having to mod my 8-pin 12v connector into a 4-pin 12v connector for my board, and having to use a PCI-E power adapter for the videocard, the powersupply seems to be working fine. One thing I’m worried about though is that I can hear the pitch of the sound my computer fans make change depending on the load of my system. According to CPUZ (latest beta), my Core Voltage drops from 1.376 to 1.328 under load. Stability doesn’t seem to be affected.

Could it be that I’m nearing the edge of what the powersupply can handle? I’m worried because I’d like to replace my X850XT with something like an 8800GTS pretty soon.

The old 550 can’t be too bad. I don’t think I ever realized how much power my old Xeon rig sucked up until I tried to put my spare parts back into a 2nd system powered by an Antec Earthwatts 380. Even though the Antec380 has a 24-pin connector and dual 12v rails, it just wasn’t enough whereas the 550 powered that rig and all my hard drives for 4 years.

[oakstave]

I think what you're hearing is normal. 550W is plenty for that set up, and a new VC. If you're going SLI, your gonna need a new one. The dip in voltage is a little disconcerting, but if you're not seeing stability issues: Rock on.

[Omsion]

Load = heat = fans spinning faster, that parts all as usual.

I'm not experienced with PSUs, so I can't tell you much about the voltage drop, though

[RollingThunder]

I built my old Xeon rig back in 2003, and I went with an EPS12V powersupply because back then they were the only ones that had 24+8 connectors. I recently upgraded to an overclocked Q6600 rig but kept my old powersupply. It seemed to me like it should be enough, since it had many of the same features of modern supplies (24-pin, dual 12v rails, etc).

http://www.fsp-group.com/english/1_product/2_detail.asp?mainid=2&fid=54&proid=33

Other than having to mod my 8-pin 12v connector into a 4-pin 12v connector for my board, and having to use a PCI-E power adapter for the videocard, the powersupply seems to be working fine. One thing I’m worried about though is that I can hear the pitch of the sound my computer fans make change depending on the load of my system. According to CPUZ (latest beta), my Core Voltage drops from 1.376 to 1.328 under load. Stability doesn’t seem to be affected.

Could it be that I’m nearing the edge of what the powersupply can handle? I’m worried because I’d like to replace my X850XT with something like an 8800GTS pretty soon.

The old 550 can’t be too bad. I don’t think I ever realized how much power my old Xeon rig sucked up until I tried to put my spare parts back into a 2nd system powered by an Antec Earthwatts 380. Even though the Antec380 has a 24-pin connector and dual 12v rails, it just wasn’t enough whereas the 550 powered that rig and all my hard drives for 4 years.

Rice,

I agree that as the load and heat increases, the faster your fan should turn increasing noise. Some power supplies are more pronounced than others. Perfectly normal.

I wouldn't be too concerned about your core voltage readings using software, they aren't that accurate. A DMM will tell you for sure but some drop in voltage under stress is normal.

Your power supply should be more than enough but efficiency and electrolytic capacitor aging occurs with age, it's four years old and it's hard to determine what this loss is without significant tests. Your Core Duo probably requires less power than your Zeon although I don't have the numbers in front of me.

Personally, I also would keep using your old power supply keeping an eye (and ear) on it for signs of failure or stress but according to the "numbers," you should be just fine. Even with a vid upgrade to an 8800GTS, it shouldn't even be close to reaching its capacity. Just keep in mind its age and the unknowns mentioned above.

[GotNoRice]

Load = heat = fans spinning faster, that parts all as usual.

I'm not experienced with PSUs, so I can't tell you much about the voltage drop, though

Yeah I should have stated, all my fans are hooked up directly via adapters, so they shouldn't be adjusting speed automatically.

The pitch of the sound actually gets lower under load, as if the fan is spinning slightly slower, as you might expect with a voltage drop issue.

I was thinking about getting a small 5.25" bay powersupply or something along those lines and maybe just using it to power the fans and a hard drive or two, see if that made any difference.

[JamesXP]

http://www.mini-box.com/s.nl/it.A/id.417/.f


:P