In the office i work at we do mostly Autocad work.
We have Dell Precision 390 work station towers -
core 2 duo @ 2.4 ghz,
8gb Ram (4x 2gb)
320gb HD (7200rpm)
2 CD/DVD drives
Stock motherboard and power supply which im pretty sure is 370 watts (might have been 380, i just dont feel like opening it up again right now).
Even when we got them which was end of 2007/early 2008 i remember thinking the PSU seemed low because i had just built my own with a 550 watt PSU.
We really need larger graphics cards so we purchased a couple without considering the Powersupply until i was reading the side of the box and it recommended having a 500w PSU....
They are Saphire Radeon 6870 cards.
The question now is whether its worth also buying two new PSUs or just returning the cards and thinking about ditching these machines all together (a tough call since they are just barely 4 years old).
It depends on how much you want to spend. I can't imagine needing a better PC to use autocad (the last time I used autocad was for a requirement for my Industrial Technology degree in college back in 2003, so maybe im wrong).
But its the difference between adding a couple hundred bucks give or take to the cost of the new cards or dropping considerably more money on 2 completely new systems.
The problem here is you will probably have to get the PSU through Dell, as I doubt the PSU cubby is ATX form factor.
The OEM 375 watt power supply is taller than the ATX12V standard of 86mm (3.4"). The screw mounting holes are in the standard ATX12V positions.
For a system using a single Radeon HD 6870 graphics card AMD specifies a minimum of a 500 Watt or greater power supply. The power supply should also have a combined +12 Volt continuous current rating of 28 Amps or greater and have at least two 6-pin PCI Express supplementary power connectors.
Your OEM 375 Watt power supply has a maximum combined +12 Volt continuous current rating of 30 Amps and may be electrically sufficient but it only has one 6-pin PCI Express Connector but the Radeon HD 6870 requires two. Since that power supply has only one 4-pin Molex peripheral connector you don't even have the option to use a dual 4-pin Molex to 6-pin PCIe power dongle.
The power supply upgrade is possible so don't discount it.
the dells PSU is taller than the standard which means there should be plenty of room for a newer one?
Height isn't an issue, depth can be, the Dell psu is only 140 mm deep, the space in the case is good for around 165mm before things get tight.
Cable management can be an issue also, the Dell has it's wires and connectors setup for that machine, you won't find an aftermarket unit that comes close to being the same.
Unsleeved cables make things easier http://www.newegg.com/Product/Product.aspx?Item=N82E168...