Optiplex 755 Mt doesn't turn off

Question

Good morning,

I upgrade my Dell Optiplex 755 with a cpu intel q9650 but sometimes when I try to switch off the pc. It doesn't turn off. The monitor turn off but the case stays with fan that works and the start/stop button illuminated.

Please tell me something to do . Bios is A22.

Grazie

Carlo.

savvy2 · Accepted Answer

as old as 12 years old (facts to know)

2 things right or wrong.

1: did you update the BIOS first to support all newer CPU. Version A22 was the last.2014.

2: did you ask Dell first what CPU are supported, do not guess. ok.

try this called a hard power reset

1: power off

2: pull power cord from wall. see it will turn off.

3: then push power button with line AC cord not connected.

4: SEE FANS spin for 1 second , is very very common.

5: wait 15minutes, this further discharges huge capacitors inside.

6: POWER cord back now.

7: power on and test it.

what may be wrong is the ICH10 intel chip power controller is confused, this does happen. above is fix, 1-7

also in bios make sure the power button is set for forced power off, not sleep. or anything else.

one more..... computer sevice is like that, lots of facts and details and cures.

the RTC battery is now 2007 (built) , 12 years old, they have spec, life of 7 so ,, get rid of it (new one)

then with new RTC coin cell in bios do a BIOS default click, this puts the NVram back to DAY 1.

then test the PC.

the MT has 4 LED diagnostic error light status with 4 bit error codes. do you get codes there, as covered in your manual.?

the support pages nor BIOS details pages cover CPU certified,

but if you dig you will see this.

the Q96 was not in the official book here

https://www.dell.com/downloads/global/products/optix/en/opti_755_techspecs.pdf?dgc=BA&cid=271006&lid=4970696&acd=12309188680294295

shows.

Intel Core 2 Duo E6850 Processor (3.0GHz, 4MB L2 cache, 1333MHz FSB, vPro, VT

but this guy says that non DELL , sources say the Q9650 works.(toms) and is 95w TPD processor.

but 9650 is CORE not CORE 2.

what odd answer is that. at TOMS.? I think core and core2 mix here is bogus !

https://www.dell.com/community/Desktops-General-Read-Only/Optiplex-755-maximum-CPU-and-Ram/td-p/4273043

Charlie1979 · Answer

Thanks for the answer

There aren't specific beeps or error, the system is like a "frozen state" . I'll try to change the battery of motherboard like you said.

Here you are the specs of my Dell: CPU is Intel Core 2 Quad Q9650 @ 3.00GHz 34 °C
Tecnologia Yorkfield 45nm I wrote wrong in the other post, sorry.

Sistema Operativo
Windows 7 Ultimate 32-bit SP1
CPU
Intel Core 2 Quad Q9650 @ 3.00GHz 34 °C
Tecnologia Yorkfield 45nm
RAM
8,00GB Canale Doppio DDR2 @ 398 MHz (6-6-6-18)
Scheda Madre
Dell Inc. 0GM819 (CPU)
Grafica
CMC 17" AD (1280x1024@60Hz)
1023 MBNVIDIA GeForce GT 710 (MSI) 33 °C
Memorizzazione
223GB KINGSTON SUV500240G ATA Device (SATA-2 (SSD)) 29 °C
931GB Western Digital WD Ext HDD 1021 USB Device (USB (SATA) ) 27 °C
Drive Ottici
HL-DT-ST DVDRAM GH22NS70 ATA Device
Audio
Dispositivo High Definition Audio

Than you.

speedstep · Answer

Intel® Core™2 Extreme Processor QX9650 is not supported.

https://ark.intel.com/content/www/us/en/ark/products/33921/intel-core-2-extreme-processor-qx9650-12m-cache-3-00-ghz-1333-mhz-fsb.html

Core™2 Extreme processor requires Precision T3400

with 525W power supply.

Intel® Core™2 Quad Processor Q9650 is fine.

https://ark.intel.com/content/www/us/en/ark/products/35428/intel-core-2-quad-processor-q9650-12m-cache-3-00-ghz-1333-mhz-fsb.html

Charlie1979 · Answer

Dell doesn't show errors or beeps. It's like a 'frozen state'. My Cpu la q9650 not ad I'll try to change the batter of motherboard . Thanks

bradthetechnut · Answer

I'd like to mention the 755 tech guide, and some others, are too far back to have in print compatible CPU's and some GPU's that came out afterwards. The Q9650 was recommended to me as the top CPU by Dell Community experts or Rockstars. Modified Xeon's for the 755 and it's relatives aren't recommended.

There's also userbenchmark to test user builds. My 2nd resort if a GPU somebody wants isn't in the manual.

bradthetechnut · Answer

As speedstep said, 'Intel® Core™2 Quad Processor Q9650&#xa0; is fine.'&#xa0; I use it in my 755.Why savvy2 has issue with 'Intel® Core™2 Quad,' I don't know.&#xa0; It's not savvy.&#xa0; It's the name Intel obviously trademarked for this processor and others.&#xa0; In another post, I included a screengrab from eBay showing the processor.&#xa0; Some Xeon's were also called 'Core 2 Quad' by Intel.&#xa0; It's not made up by Joe Blow.&#xa0;&#xa0;

bradthetechnut · Answer

Back to the main point, you should be able to adjust what the power button does in the Power Management settings.

Savvy2 is right about replacing the battery, if it's too low or dead, BIOS won't remember your settings if you change any there.

Also, using your OS, like Windows, is the recommended way to shut off a computer.

speedstep · Answer

They are hard to find. ButTechnical Guide is still onlinehttps://www.dell.com/downloads/global/products/optix/en/opti_755_techspecs.pdfUSFF is the only one that doesn't support Quads.&#xa0; &#xa0;Supported Processors&#xa0;User Guide is still there.Dell™ OptiPlex™ 755Models DCTR, DCNE, DCSM, and DCCYRegulatory Model (Mini-Tower): DCSMRegulatory Model (Desktop): DCNERegulatory Model (Small Form Factor): DCCYRegulatory Model (Ultra Small Form Factor): DCTR https://downloads.dell.com/manuals/all-products/esuprt_desktop/esuprt_optiplex_desktop/optiplex-755_user%27s%20guide_en-us.pdf&#xa0;And the AMT guide is still there.https://downloads.dell.com/manuals/all-products/esuprt_desktop/esuprt_optiplex_desktop/optiplex-755_user%27s%20guide%202_en-us.pdfSetup Guide is also still online.https://downloads.dell.com/manuals/all-products/esuprt_desktop/esuprt_optiplex_desktop/optiplex-755_setup%20guide_en-us.pdf&#xa0;

Optiplex Desktops

Optiplex 755 Mt doesn't turn off

Intel® Core™2 Extreme Processor QX9650 is not supported.

Core™2 Extreme processor requires Precision T3400

with 525W power supply.

Intel® Core™2 Quad Processor Q9650 is fine.

Was this post helpful?