Dell Optiplex SFF 990 fan fail?

Question

Hi,

Six months ago I booted this Win7 64bit Pro SP1 pc to be met with a 'black-screen' cpu fan-fail message.

This coincided with me being laid up for months - just a coincidence. Anyway, the pc has been used as a storage surface ever since, couldn't get at it where it was in a niche. So it goes.

This evening I prized it out & flipped the lid off, nothing jamming the fan - only one fan I noticed - no rear fan? Nice and clean inside, no dust.

So I booted, but with the lid off, saw the fan working okay - but same message - followed by "Press F1 to continue", which I did, expecting a loop. But then the pc booted as normal

Am amazed - this pc was my 'other' workhorse, was non-plussed when it 'failed'.

Can anyone explain the false failure please?

Could a power-cut have phased the Optiplex last summer? - we get them now and then, sometimes micro duration, lasting only minutes.

Like to up this to Win10 with a new SSD, clean install - keen that it won't fail again, it's only running on half available RAM as well, can go up to 16GB, two slots free.

3.10GHz CPU i5

Thanks.

donm4599x · Answer

Try running the dell diagnostics in the bios (f-12 key maybe?). It checks the fans for the correct speed. and reports the min and max speeds it can run.

It could simply be gummed up from sitting so long.

Also double check (use magnifier glass) and re-seat the fan's connector cable a few times.

kr236rk02 · Answer

Thanks

donm4599x · Answer

Forgot to mention ... If you need more than 16 GB memory, that machine can use 8GB modules I believe. I have a 790, which is similar to 990, and it works fine with them.

kr236rk02 · Answer

'Event Viewer' shows multiple error alerts, but searching them for 'fan' or 'cpu' yielded no results. Mystery.

Do you think I'm green-to-go for the upgrade to 10 please? Just ran a complex software on the 990 & no issues.

kr236rk02 · Answer

Wow! Seriously? So max out to 32GB? Will the 990 Mobo accept that = will it 'see' the extra RAM?

speedstep · Answer

32 gig with quad rank dimms is NOT an option.

This model will also have spectre and meltdown issues that will never be patched.

https://www.crucial.com/usa/en/compatible-upgrade-for/Dell/optiplex-990-desktop

https://www.grc.com/inspectre.htm

Windows 10 works fine on these models but its not supported.

You have to use windows 7 drivers. There will NEVER be any windows 10 drivers.

https://www.dell.com/support/article/us/en/04/how13802/optiplex-990-windows-7-driver-cab?lang=en

You clean install 10 with the I don't have a key option then use windows 7 COA key.

You download the cab file and move to the my documents folder.

https://downloads.dell.com/FOLDER02161719M/1/990-win7-A10-5GWVN.CAB

You then extract the contents of the cab file using 7zip.

https://www.7-zip.org/download.html

You then update any yellow ! in device manager from my computer instead of from the internet.

Category DeviceDescription Driver Pack Release Info

Audio	Realtek ALC269 HD Audi o;Realtek ALC269 HD Au dio Codec;Realtek ALC2 69 Audio	ReleaseID: VJ0P8_A13-00 DellVersion: A13 VendorVersion: 6.0.1.5931
Chipset	Intel Chipset	ReleaseID: 3RJ4W_A01-00 DellVersion: A01 VendorVersion: 9.2.0.1019
Chipset	NEC USB3.0 xHCI	ReleaseID: 5XD8K_A01-00 DellVersion: A01 VendorVersion: 2.0.30.0
Chipset	Intel Management Engine 7.0 Components for 5 MB	ReleaseID: MPGY4_A05-00 DellVersion: A05 VendorVersion: 7.1.70.1205
Communication	Foxconn Serial/Paralle l port PCIE add-in-car d Driver	ReleaseID: DMD90_A04-00 DellVersion: A04 VendorVersion: 7.2.0.0
Dell Data Protection	STMicron device driver for Dell Data Encrypt ion Accelerator Card	ReleaseID: DellVersion: VendorVersion:
Dell Data Protection	Dell Data Protection \| Access	ReleaseID: X1C1N_A00-00 DellVersion: A09 VendorVersion: 2.3.00003.072
Input	Dell Smartcard USB Key board	ReleaseID: 207T0_A00-00 DellVersion: A00 VendorVersion: 4.0.8.5
Network	Wireless 1520 802.11n MiniCard WLAN for Desk tops;Wireless 1520 802 .11n PCIe WLAN for Des ktops	ReleaseID: C74RH_A36-00 DellVersion: A36 VendorVersion: A36
Network	Broadcom BCM95722 PCI- E NIC	ReleaseID: GX1WC_A00-00 DellVersion: A00 VendorVersion: 16.4.0
Network	Intel 825xx 10/100/100 0 Ethernet controller; Intel Ethernet Connect ion I2XX;Intel I2xx/82 5xx Gigabit Platform L AN Network Device;Inte l I2xx/825xx Gigabit E thernet Controller;	ReleaseID: NNGMH_A08-00 DellVersion: A08 VendorVersion: 18.1.0.0
Security	This is the UPEK Windo ws Biometric Framework (WBF) Driver supporti ng UPEK External USB F ingerprint Reader devi ces attached to system s with Windows 7 Opera ting Systems.	ReleaseID: M7XVP_A00-00 DellVersion: A00 VendorVersion: 1.5.0
Storage	Intel Rapid Storage Te chnology (Pre-OS Insta ll);Intel Rapid Storag e Technology	ReleaseID: 3H23X_A07-00 DellVersion: A07 VendorVersion: 10.1.0.1008
Video	AMD Radeon HD6670(1G G DDR5)	ReleaseID: 7RG72_A01-00 DellVersion: A01 VendorVersion: 8.80
Video	Intel HD Graphics 2000 /3000;Intel HD Graphic s 2000/3000/4000;Intel HD Graphics 4000;Inte l HD Graphics 2000/250 0/3000/4000;Intel HD, HD 2000/2500/3000/4000	ReleaseID: XGPWM_A12-00 DellVersion: A12 VendorVersion: 9.17.10.3040
Video	AMD Radeon HD6450(1G D DR3);AMD Radeon HD6350 (512M DDR3).;AMD Radeo n HD6450(1G DDR3).	ReleaseID: WPCTP_A00-00 DellVersion: A04 VendorVersion: 8.922

donm4599x · Answer

Use ddr3 8GB modules. Non ecc, non registered, non buffered, 2Rx8. (just plain vanilla memory intended for desktops). I was able to get them on ebay auctions for $15 used. Some folks say it's impossible, only because dell didn't originally sell the machine with them, but many of us are using 8GB modules happily.

I haven't run across 4 rank (quad rank) modules, but I would avoid them if you see any. I guess they would called 4Rx something.

kr236rk02 · Answer

Success! Now have 16GB Ram, will up to 32GB when I have completed the upgrade!

Optiplex Desktops

Dell Optiplex SFF 990 fan fail?

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