Question Optiplex 745 SFF with Core 2 Quad Q6700 not really working properly ?

[alexborex]

Hi, i've recently upgraded my Optiplex 745 SFF to a Core 2 Quad Q6700 (upgrade from a Core 2 Duo E6420), and the system is not really working properly with it.

It always runs the fans at full speed, and Windows 10 only detects 2 cores and 2 threads, which is not normal.

This only happens with the Quad, reverting back to the Duo E6420 makes the system work properly again.

The Quad should work on my Dell, as i've seen videos online showcasing this CPU working quietly at 4 cores in the same SFF version.

As for the other specs, it has:
MSI GeForce 210
6 GB RAM
128 GB SSD
BIOS 2.6.6.

What could be the culprit?

 

[Eximo]

Try clearing the CMOS after putting in the new CPU. Check for any BIOS updates Dell released for the board.

Make sure you have an appropriately sized CPU cooler.

 

[alexborex]

Try clearing the CMOS after putting in the new CPU. Check for any BIOS updates Dell released for the board.

Make sure you have an appropriately sized CPU cooler.

I have tried resetting the CMOS multiple times, yet it didn't do anything; the system still sounds like a jet engine and the CPU still shows 2 cores/2 threads.

The BIOS is the most recent version there is.

 

[ex_bubblehead]

CPU's are not plug and play components. You have to do, at a minimum, an in place reinstall of the OS.

 

[alexborex]

There are several potential issues that could be causing the problem you're experiencing. Here are a few possibilities:

1. BIOS incompatibility: The Q6700 is a newer CPU than the E6420 and may not be fully supported by your BIOS version. Updating the BIOS to the latest version could resolve this issue.
2. Power supply: The Q6700 has a higher TDP (thermal design power) than the E6420, and your power supply may not be able to handle the increased power requirements. Upgrading the power supply to a higher wattage could resolve this issue.
3. Cooling: The Q6700 generates more heat than the E6420, and your cooling system may not be sufficient to keep the CPU at safe temperatures. Upgrading the cooling system to a better heatsink and fan could resolve this issue.
4. Windows 10 not detecting all cores: This could be due to a driver or software issue, check if the motherboard drivers are up to date, if not update them.

It's also worth noting that some Dell Optiplex models have a BIOS whitelist that only allows certain CPUs to be used. If your Dell Optiplex 745 SFF has this restriction, then using the Q6700 will not be possible regardless of the above solutions.
Keep in mind that this is not an exhaustive list and there may be other reasons why your system is not working properly with the Q6700.

1: I have BIOS 2.6.6, the latest available.
2: I also tried an external 450W PSU, and the same thing happens, not to mention i also tried a Pentium D 925 which consumes a good deal.
3: How could i upgrade the cooling though? I don't think there is another cooler for the SFF.
4: Hmm, i tried the chipset driver and it wouldn't install on 10, on 7 it did install but no change.

By now, i'm positive it's a BIOS issue, probably it has the whitelist thing. What can i do in that case?