Vostro 3500 running Windows 7 without problem, then upgraded to Windows 10.
CPU maxed out at 38% regardless of Power Options.
Eventually traced to BIOS setting: SpeedStep [Enabled].
The HM57 chipset in the Vostro 3500 does not appear to be supported by the latest Intel® Chipset Device Software (INF Update Utility) but the 'Unknown Error' failure it gives is not particularly helpful. Using the latest chipset driver that does not fail to install has no effect on the problem behaviour.
Disabling SpeedStep results in normal CPU operation.
Q: Has anyone duplicated this problem on a Vostro 3500 / HM57 chipset?
Q: If so, has anyone found a 'better' solution?
Unfortunately, there are no Windows 10 drivers for this computer from Dell.
Dell is not testing or developing Windows 10 drivers for this product. If you choose to upgrade, some features, applications, and connected devices may not work as expected.
Disabling Speedstep IS the best step. Speedstep is usually the reason for all CPU speed problems.
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Have to agree that SpeedStep because of its more aggressiveness towards power saving. Will tend to favor that more then performance. You can however also set the power management in Windows to performance which also helps this if you don't care to mess with bios settings. Many gamers feel that there is a slight lag in adjusting clock rates with SpeedStep no matter what Intel says. Just remember your heat on a notebook will increase with SpeedStep disabled.