I have a Dell Optiplex 755 USFF that I would like to upgrade. According to some techspecs that I found on the Dell site this particular flavor of 755 can support up to an E6850 (65nm). I would like to use the E8400 Wolfdale ( its' 45nm counterpart with the same clock and fsb, but more cache) since I believe it will also run cooler in the small confines of the USFF case. Although not officially supported on the techspec list I found, I see that on both the Dell Financial Services Site and the Dell Auction Site this same configuration is offered in multiple units with the E8400 installed. Can I take this as a confirmation that it would be OK to upgrade to the E8400 in the Opti 755 USFF? Thanks!
PS I already have the E8400 in another mobo so it is not a matter of which to get, only on whether I can use the E8400 in the 755 USFF. If I cannot use the E8400 then I will just keep the current cpu in place, but I'd really like to upgrade using the E8400 if it is possible. The mobo currently has the A11 Bios.
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The E8400 is supported by the Q35 chipset on the 755, which isn't always enough alone to make it work, but together with the facts that 1) the E8400 was launched about 6 months after the processors on the documented "supported" list, and presumably after that doc was published, and 2) systems are configured out there with that CPU would lead me to say that the E8400 will work in the 755.
The latest BIOS version is A21, and while none of them from A12-A21 mention anything about CPU support ... if you have any problems, that would be the first thing to look at, as some undocumented support may have been added.
The only harm in trying the swap is damaging some internal part during the swap. There is no harm in trying the processor at BIOS version A11 - the worst that will happen is your system won't POST (black screen, etc.) until you do update it (provided there is even undocumented code addressing processor compatibility), or change it back. Of course, under warranty, there's no harm in updating the BIOS either, in the extremely unlikely event that the BIOS flash goes bad.
The 755 uses the intel® Q35 express Chipset
Spec says so at Intel so With the correct Bios I would say Yes no problem.
Processor Type - Intel® Core™ 2 Quad - 1066MHz FSB, LGA 775, 8MB L2 cache,
Intel® VT, Enhanced Intel SpeedStep® Technology, Intel® 64 and Execute Disable Bit (Q6xxx series)
Intel® Core™ 2 Duo - 1333MHz FSB, LGA 775, 4MB L2 cache, Intel® vPro™ Technology, Intel® VT, Intel® TXT, Enhanced Intel SpeedStep® Technology, Intel® 64 and Execute Disable Bit (E6x50 series)
Intel® Core™ 2 Duo - 800MHz FSB, LGA 775, 2MB L2 cache, Enhanced Intel SpeedStep® Technology, Intel® 64 and Execute Disable Bit (E4000 series)
Intel® Pentium®- 800MHz FSB, LGA 775, 1MB L2 cache, Enhanced Intel SpeedStep® Technology, Intel® 64 and Execute Disable Bit (E2000 series)
Intel® Celeron®- 800MHz FSB, LGA 775, 512MB L2 cache, Intel® 64 and Execute Disable Bit Chipset Intel® Q35 Express Chipset (ICH9DO)
Many many thanks 'flash for the quick responses today and your help. FYI the unit is currently running a Xeon3070 with no issues and it isn't on the official Dell compatibility list either--but since it is a twin to the E6700 I didn't have as much hesitation with that swap as I did jumping from 65nm Conroe down to 45nm Wolfdale.
Also thanks Speedstep for the elaboration on the Q35 chipset, I knew it would support the cpu but as is known sometimes OEM vendors modify their bioses so I asked to see if anyone knew firsthand if Dell had "dampened" the compatibility for system stability reasons in the USFF version.
The power supply for the USFF is 150W not 270W so for many processors I would say the answer is not clear.
NOT UPDATING BIOS TO A21 could be a real issue.
130W processors Are not going to work in a USFF with 150W power supply,
E6850 is ok.
Intel® Core™2 Duo Processor E6850
(4M Cache, 3.00 GHz, 1333 MHz FSB)
VID Voltage Range
The QX8200 May not work due to
Core stepping M1
I also think the 130W and 150W cpu's would require a Tower with Greater than
305W power supply AND the Copper heatpipe heatsink.
These are the Quads we validated -
N652J 3.00GHz YorkfieldQuad Core Q9650, 12MB Q9650
|Manufacturing technology (micron)||0.045|
|Number of cores||4|
|L2 cache size (MB)||12|
Enhanced SpeedStep technology
Execute disable bit
Extended Halt state
Extended Stop Grant state
Thermal Monitor 2
Trusted Execution technology
|Core voltage (V)||0.85 - 1.3625|
F886J 2.83GHz Yorkfield Quad Core Q9550 12MB, 1333FSB, E0
N650J 2.66GHz Yorkfield Quad Core Q9400, 6MB, 1333FSB, R0
MP627 2.66GHz Kentsfield Quad Core Q6700, 8MB, 1066FSB, G0
Dell recommends applying this update during your next scheduled update cycle. The update contains feature enhancements or changes that will help keep your system software current and compatible with other system modules (firmware, BIOS, drivers and software).
UPDATING the bios must be done BEFORE trying another cpu.
|Manufacturing process||0.045 micron|
V core0.85V - 1.3625V
CPUs, related to Intel Core 2 Quad Q8200
|Intel Core 2 Quad family, Socket 775|
|Intel Core 2 Quad Q9500||4 / 4||2.83 GHz||6 MB||95 Watt||SSE4, VT, ESS|
|Intel Core 2 Quad Q9505||4 / 4||2.83 GHz||6 MB||95 Watt||SSE4, VT, TXT, ESS|
|Intel Core 2 Quad Q9505S||4 / 4||2.83 GHz||6 MB||65 Watt||SSE4, VT, TXT, ESS|
|Intel Core 2 Quad Q9450S||4 / 4||2.66 GHz||12 MB||65 Watt||SSE4, VT, ESS|
|Intel Core 2 Quad Q9450||4 / 4||2.66 GHz||12 MB||95 Watt||SSE4, VT, TXT, ESS|
|Intel Core 2 Quad Q9550||4 / 4||2.83 GHz||12 MB||95 Watt||SSE4, VT, TXT, ESS|
|Intel Core 2 Quad Q9550S||4 / 4||2.83 GHz||12 MB||65 Watt||SSE4, VT, TXT, ESS|
|Intel Core 2 Quad Q9700||4 / 4||3.16 GHz||6 MB||95 Watt||SSE4, VT, ESS|
|Intel Core 2 Quad Q9705||4 / 4||3.16 GHz||6 MB||95 Watt||SSE4, VT, TXT, ESS|
|Intel Core 2 Quad Q9650||4 / 4||3 GHz||12 MB||95 Watt||SSE4, VT, TXT, ESS|
CPUs, related to Intel Core 2 Extreme QX9650
|Intel Core 2 Extreme family, Socket 775|
|Intel Core 2 Extreme X6800||2 / 2||2.93 GHz||4 MB||1||75 Watt||SSE4, VT, ESS|
|Intel Core 2 Extreme QX6700||4 / 4||2.66 GHz||8 MB||1||130 Watt||SSE4, VT, ESS|
|Intel Core 2 Extreme QX6800||4 / 4||2.93 GHz||8 MB||1||130 Watt||SSE4, VT, ESS|
|Intel Core 2 Extreme QX6850||4 / 4||3 GHz||8 MB||1||130 Watt||SSE4, VT, ESS|
|Intel Core 2 Extreme QX9770||4 / 4||3.2 GHz||12 MB||1||136 Watt||SSE4, VT, ESS|
|Intel Core 2 Extreme family, Core micro-architecture, Other sockets|
|Intel Core 2 Extreme QX9775||4 / 4||3.2 GHz||12 MB||2||150 Watt||SSE4, VT, ESS|
Just to be clear, the power supply for the USFF is 220 W according to the tech specs chart, not 150W.
I am running the latest BIOS which is A22, so that should not be a problem at all.
Also, the E8400 is essentially the same thing as the E6850, just with the 45 nm process instead of the 65 nm. So the power consumption should be the same, and the power should not be an issue. The real issue in question is whether or not Dell has added support for the 45 nm Core 2 Duos in their BIOS, because they are supported natively on the chipset by Intel.
"Just to be clear, the power supply for the USFF is 220 W according to the tech specs chart, not 150W"
The external Brick is not the same as the power rating for the INTERNAL MOTHERBOARD VRM's
This is also why the Quads are Not listed as compatable with the USFF.
This is not to say that it wont work. I dont know fer shuure cuz I aint got one.
HOWEVER this is also not a Guarantee that it DOES work.
Without Updating the Bios to A21 it is highly LIKELY that it will not post OR it will simply state unsupported processor and either HALT or make you Press F1 to continue Each and every time.
avibber56, I didn't end up installing it and ended up having a mobo replacement due to the YROD, luckily it happened before my warranty ran out. I was too apprehensive to attempt to install the E8400 just in case it would damage the replacement. mobo, but it has been running with the Xeon ever since, abeit with USB issues. I have seen many Optiplex 755 USSF units for sale on ebay with the E8400 installed though so I'm thinking that they will work, I just lost the initiative to install it. I also have a Q9450 but even if the mobo will support it I don't think the limited stock cooling will keep it stable, it would probably overheat in those small quarters with that stock hs/f.
You are posting about a USSF but the Dell site only shows a bios for the USFF up to A19, so if you are using the A21 or A22, are you using SFF bios instead of the USSF?