Need detail on installing 2nd HD in Optiplex 755 Desktop

Bump.

The DT, SFF, USFF models will have a thermal message.  The tower model does not care about the Drive Type.  it is due to "thermal considerations".

Dell 755 Desktop is configured to reject anything but a Western Digital or Samsung hard drive, claiming it is due to "thermal considerations".  This is for the Desktop and SFF and USFF models.

'HDD replacement is not valid' Message on Dell Optiplex Computer - KB Article - 329305 | Dell

Hey Speed - thanks.

I think I'm going to buy a WD Blue or Green 1TB HDD with up to 6Gbps transfer speed and 64MB cache.  Probably SATA 3 but I understand it will also handle a lower SATA if that's what my Optiplex 755 from 2008 handles.  Will be a big increase in capacity from my current 160GB HDD that came with the machine.

I'll open the machine this weekend to see about cables and brackets.

But any thoughts about my third question?

I have installed Windows 7 64 Bit on plenty of OptiPlex 755's.

To install follow the instructions here:

http://dellwindowsreinstallationguide.com/a-clean-install-of-windows/

Obviously do not format with DBAN, or delete any partitions on the old drive etc. WIndows 7 will then automatically be setup to dual boot Windows XP and Windows 7. Its possible for you to install a SSD which should have less heat although you may still get the warning if you have USFF.

Natakuc, Speed and Philip - Thanks very much for your posts.  New twist:

I happen to have at home a Momentus XT HYBRID solid-state+normal HDD for my wife's old Dell Latitude D830 laptop that she doesn't use any more.  It's a 2.5" internal drive for laptops - 500GB, 7200 RPM, 32MB cache, 3Gb/s data rate, Serial ATA interface with NCQ (Native Command Queuing).

Could I use it as the new HDD in my Optiplex 755 Desktop? 

1)  What type of bracket would I need so that it sits firmly in place in the Optiplex 755 Desktop (which expects a 3.5" HDD, not 2.5")? 

2)  And what type of cable?

Now, I think heat is indeed a problem.  Shortly after I bought that Momentus XT (in Dec 2012?) and put it in her laptop to replace her original Dell (Fujitsu) 80GB normal HDD, her laptop blew up forever.  She had been complaining it was getting hot, and I suspect that heat from this Momentus XT (which I did not know could be an issue) caused other stuff inside to melt or break.

3)  Therefore, if I do use this Momentus XT as the new HDD in my Optiplex 755 Desktop, will my Dell BIOS (A22) reject it as a heat risk? 

4)  If it does, will I have the option of booting anyway?

5)  If yes to #2, will I have the option of setting the BIOS to never bug me about heat risk again so that I can reboot remotely and the reboot won't get stuck at the BIOS heat risk alert?

6) Is it easy to increase the fan in the Opti 755 case so that actual heat is actually dissipated?  I like to leave my home Opti 755 on all the time so I can remote in for personal emails.

7)  If there are good answers to all the above, what do I need to do at the start to reformat or wipe the Momentus XT?  (I ask only because maybe I read that one doesn't wipe or clean up a hybrid SSD+normal HDD the way one does to a fully normal HDD.)  But maybe I don't need to do anything because the install of Win 7 will wipe the Momentus XT anyway?

Thanks again!!  (Hey, if it were easy, it would be boring.)

Philip and friends - Slowly but surely -

1)  Now, some fine print in the Dell guide for the Optiplex 755 says that when an additional hard drive is added to the machine, the SATA cables have to go into the SATA sockets on the board in order - first the HDDs and then the optical CD-DVD drive.  Right now, my only HDD is connected to SATA 0 on the board and my optical CD-DVD drive is connected to SATA 1.  The Dell instructions mean that when I add the new second HDD, it must be connected to SATA 1 and the optical CD-DVD drive cable must be moved to SATA 2.

Well, that's OK, but it means my original plan to DISCONNECT my existing HDD with my Win XP before installing Win 7 on the new second drive might not work.  In detail:  First, I was going to physically install the second HDD and connect it to SATA 1 (moving the optical CD-DVD drive cable to SATA 2), turn on the computer (still in Win XP) and make sure the computer can see and work with the blank second drive AND label it NOT as C:\ (which I'll keep for the XP) but as something else - maybe Q:\ (or maybe the PC will automatically label it something else).  Second, I was going to turn the computer off, DISCONNECT the original HDD with Win XP from SATA 0, turn the computer on and install Win 7 on the second HDD as Q:\ drive.  But maybe because it is connected to SATA 1 and there is now nothing in SATA 0, the PC won't see anything ??

Maybe I am wrong about all of this and I can leave everything connected?  How do I know that when I install Win 7 I won't accidentally overwrite my existing HDD with XP?

Reminder that my goal is to have a dual-boot option, keeping the existing XP drive as C:\ AND the PC knows that if I don't elect any of the options on boot-up it should default-boot into Q:\ Win 7 after some seconds.

I'm probably going off in the wrong direction, of course.  All guidance gladly accepted!!

2)  I was also surprised to discover that my existing HDD from 2008 is a WD "Velociraptor" model WD1600HLFS boasting RPM 10,000.  Since I want Win 7 to feel as snappy as my XP, should I buy a similar 10,000 RPM "Velociraptor" as the new second HDD?  What are the maximum HDD specs that this Opti 755 will support?  (No point buying 6Gbps if the Opti will only handle 3Gbps - but I don't know that.)

Thanks again.  Hope this is helpful to other non-techs.