[swetnich]

Was wondering if you could help me out. I bought additional RAM and a new graphics card for my sons computer for Christmas and it is to big (size)for the computer, it will fit in the slot but is to tall and the top will not go back on. I added the 8gb RAM but it is telling me that it has 12gb of RAM but only 3.12 gb is useable??? He has a OptiPlex 790 small form, windows 7, intel core i5. He wants to play minecraft and counter strike with no lag time and increased fps. Please any help would be amazing. I bought him a GeForce gtx 650 pny graphics card. I thought I did enough research but failed....

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Is he using Windows 7 32 Bit?

[Alan1998]

Is he using Windows 7 32 Bit?

[swetnich]

yes he is

[terry1966]

as mentioned above the reason for it only being able to use 3.12gb of ram is a physical 32bit operating system limitation and you need to be using a 64bit operating system before all the fitted ram can be utilized, as for the graphics card problem you can either return it and buy one that will fit into the small case or buy a bigger case and transfer every across into that (my choice.).

 

i should think your going to need a new more powerful power supply unit (psu) too, i believe the psu in that OptiPlex 790 system is 260watts and that graphics card needs at least a 400watt psu according to the specs here:- http://www.geforce.c.../specifications

 

so really to get everything working you need to.

1:- buy a good new 400watt psu. eg:- http://www.dabs.com/...8BV9.html?src=2

2:- buy a bigger case. eg. :- http://www.dabs.com/...294942088&src=3

3:- install 64bit windows 7 . more info here :- http://windows.micro...s#1TC=windows-7

 

[swetnich]

Thank you very much for your help I am going to look into all the above you suggested because it is looking like I can not return the graphics card since I bought it online. How hard is it for some one who doesn't know computers that well to transfer everything over to a bigger case??

[terry1966]

it usually isn't that hard depending on case, no harder than inserting the new ram you bought really, it's just a few screws and some simple unplugging and plugging back in of cables.

 

best advice is first to unplug all power then press and hold power on button for a second or so to discharge all remaining current in the system before doing anything.

then to take good pictures on a smart phone of every step you make before and after making it, so you know what went where when it comes time to putting everything back together again in the new case.

don't remove the cpu heat sink and cpu, big thing near top of motherboard usually.

 

find where it says the motherboard make model on the motherboard itself, usually written somewhere in between the pci-e slots and find a manual for it online.

this will help you to locate and find things on the motherboard telling you what each and every connection is for in case you run into any problems when it comes time to connecting the cables from the new case to the motherboard.

 

important thing is to make sure the motherboard standoffs (motherboard is screwed to these) are fitted in the correct place in the new cases motherboard tray with no extra's (may short things out) instructions for this usually come with the case.

now the motherboard is screwed in place, everything else is then more or less just a case of plugging things back in exactly the same way they were in the old case.

 

also had a thought about the 32bit physical ram address limitation and remembered windows had a work around called pae that may save you needing to install a 64bit windows 7 os (i would tho.) more info on that here. :- http://msdn.microsof...6(v=vs.85).aspx

 

memory was playing tricks with me and you still need to install win7 64bit os to use all your installed ram.

 

 

forgot to mention a very important step and safety precaution against static, you want to make sure you are always touching the metal of the case or buy and wear an anti static strap :- http://www.amazon.co...e/dp/B000L98002 when removing or installing any pc components. static can kill your hardware without you even seeing it.

Edited by terry1966, 27 December 2014 - 12:57 AM.

[swetnich]

So another problem I was having is when I would put the graphic card in it has an attachment for the 6 pin but the computer doesn't have any place to plug the two 4 pin into or an 6 pin from the computer to the card? And the drivers will not download from the cd to the computer, the computer doesn't see the graphic card?

[terry1966]

good job really.

 

ok joking aside, when you get the new power supply you will find it will have the required power cables you need for the graphics card.

the card wasn't seen by the computer because it isn't getting any power and like i stated in the first post that power supply unit doesn't have enough energy in it to power both the pc and the card so if you did have the cables available on that power supply unit then all that would probably happen is the computer would shut itself down when turned on or under load.

 

i'd take the card out and put it back into it's box until you have bought the new case and power supply, otherwise you may risk damaging it with static or something before you have got it up and running.

 

also here's a guide explaining about safety and static and stuff when working on pc's :-  http://forums.whatth...howtopic=103649

 

[swetnich]

Ok great I have already put it back in the box....I was done trying to mess with it. Thank you again now it all seems to make some sense to me. Happy New Year!

[terry1966]

happy new year to you and your family too,

tell your son he might be a bit disappointed now but the extra wait will be worth it.

 

[swetnich]

Thank you! I just got back from best buy and they told me that his computer would not support hooking up the power supply and the graphics card...it was not doable. I wish I knew more about this stuff. Maybe I should just look into a new computer for him

[terry1966]

no idea exactly what they told you but it is most definitely doable, just not in that case and with the current power supply.

 

here's a video that may help you. :- http://www.dell.com/...m-board-en.aspx

 

 

is there any pc repair shops around near where you live, if so and your wary of doing things yourself take it to them and ask how much it would cost to transfer everything from that pc into a new case with the required power supply unit to run the graphics card you have, and then get them to do the job for you. i expect they could buy everything you need and do the job for about $200 or less including their labour costs.

Edited by terry1966, 27 December 2014 - 05:26 PM.

[terry1966]

how you getting on?

 

had a thought that might help you, this is a video showing how to build a pc.

 

now all your parts are going to come from your old pc except the case and new power supply and of course the new graphics card.

 

the cpu and heatsink are already going to be connected to your motherboard, so that's one thing you won't have to worry about, just make sure not to take them off the motherboard when taking the parts out of the old case.

 

things may not look exactly the same case wise or fit exactly the same, but the steps as seen in the video are pretty easy and straight forward and more or less the same for every pc built today with only slight differences, for example to fit the dvd drive on some cases it may require being screwed on, while other cases it may just need the pressing of push button to lock it in place..

 

so it's just a case of reversing the build process to take the parts out of your old case then follow it again in order to build it again in the new case with the new power supply unit and graphics card, discarding the old case and power supply.

 

best buy are a bunch of idiots in my opinion.

 

and here's a link to videos of the pc you have, so should have all the info on how to go about taking the parts out of it.

https://www.youtube....ptiPlex 790 sff

 

 

after saying all that it might be me that's the idiot because i can't find anywhere where it says if the 790 motherboard is a standard type with the holes in the correct place to fit in a case big enough to house that graphics card, and it's been years since i've worked on an oem machine and never a dell optiplex 790 sff. of course a case could be made to fit the motherboard with a bit of drilling, but it's a lot more work than a simple swap like i first thought if it's not a standard form factor size like micro atx.

Edited by terry1966, 30 December 2014 - 04:10 AM.

[swetnich]

I haven't done to much other than research new computers....Great thank you for the video I will take a look and see how hard it might be....or easy for that matter. Yeah I didn't have the best feeling from the guy at best buy either. Thank you so much for everything. Happy New Year!!

Edited by swetnich, 30 December 2014 - 11:16 AM.

[terry1966]

you too, build your own it's not that hard and there are lots of guides and videos on the internet to help you choose the parts,

or specify a budget in a new topic and the people here can suggest a parts list that will go well together.