PCI-Express power limits

I am attempting to turn an Opti 755 desktop into an ersatz small workstation for an architecture student doing CAD, rendering and 3D design.  I have upped RAM to 6GB with further upgrades to 8GB and a Core 2 Quad in reserve.  I have an NVidia Quadro 600 that physically fits, however it is rated to draw 40 watts whereas stenciled on the motherboard next to the PCI-e slot it says not to exceed 25 watts. Is this limit dictated by the 280 watt power supply, or by the motherboard?  Adding up power draw from everything installed, including the Quadro, stays under 200 watts, and that is maximum draw, i.e. at startup currents for the HDD and DVD.  It actually seems unlikely that these would be in startup mode while the GPU is breathing hard at CAD or rendering.  so I'm thinking the power supply should be  adequate.  Also, PCI-e slots are supposed to be able to supply up to 75 watts. So, should I be concerned or not?

If you want to build a cheap powerful workstation you don't use slim desktop Optiplex machines if you'd used a mini tower that would not be a problem. With the slim dell's the max power draw for the PCI-E is 25W because the motherboard is limited to that in order to use the little bit of power the power supply provides. And perhaps the worst part of this you can't do much except using a not so good GPU that draws 25 watts.

ElPro999 -

What actually happens when you exceed 25 watts?  Do you fry something, does the MB stop working gracefully, or what?

Most likely the result would be a "no post" scenario. Just removing the video card should allow the system to then post correctly. I am not sure if a 10 year old PCIe 1.0 slot will actually provide 75w? In this model, we only validated the Low Profile Ati Radeon HD 2400 XT and Low Profile Ati Radeon HD 2400 Pro which only use 25w.

There is no justification for using Optiplex when Precision T3400 and T3500 units are Available everywhere.

https://www.amazon.com/Dell-Precision-T3400-Workstation-2-33GHz/dp/B0087I7RO4/

 Dell Precision T3500 PC Desktop Intel Xeon 2.8GHz W3530, 500GB HDD, 8GB Ram. Video card Quadro FX 580

https://www.amazon.com/Dell-Precision-Desktop-Ram-Windows-installed/dp/B00CLJHG78

" Optiplex with a Core 2 Duo that can be upgraded:  Quad CPU, 8GB of RAM, and a workstation video card such as a Quadro 600, yet still cost under $100."  Unless the optiplex is free I'm still not convinced this is a good path. Performance and Reliability wise It does not appear that you are taking all costs into consideration.

$127 with free shipping isn't a Lot.

The Optiplex and quad core cpu's with Quadro 600 I do not have a source for under $100.   Windows 7 pro alone is worth more than $100.

https://www.amazon.com/Dell-Precision-T3400-Workstation-2-33GHz/dp/B0087I7RO4

These are all free shipping

These are mostly financially-challenged inner-city kids studying architecture at a 2 year community college.  Dell Precisions mainly sell for $200 and up on Craigslist and would usually still need upgrades.  Most anything bought on Ebay or Amazon would entail expensive shipping as well.  So the target remains an Optiplex with a Core 2 Duo that can be upgraded:  Quad CPU, 8GB of RAM, and a workstation video card such as a Quadro 600, yet still cost under $100.  I'm thinking the solution is simply to go with the MT configuration instead of desktop.  That should see these students through their program and somewhat beyond.  When they are in a profitable practice they can afford more.

Opti 7xxs with Core2 Duos go for $20-30 at swap meets.  Mostly without hard disks, so that's another $10 for 150-250 GB.  Academic licenses for W10 must be about $5 each.since LAUSD offers them to staff for that, and might be needed for the T3400 anyhow.  At this point we are neck-and-neck and I've only spent $40.  Both could use upgrades to 8GB, quad CPU and better graphics.  The included 512MB FX 1700 is sub-marginal for the software being taught; it only supports DirectX 10.

Opti 7xxs with Core2 Duos go for $20-30 at swap meets.  Mostly without hard disks, so that's another $10 for 150-250 GB.  Academic licenses for W10 must be about $5 each.since LAUSD offers them to staff for that, and might be needed for the T3400 anyhow.  At this point we are neck-and-neck and I've only spent $40.  Both could use upgrades to 8GB, quad CPU and better graphics.  The included 512MB FX 1700 is sub-marginal for the software being taught; it only supports DirectX 10.

Dell precision machines are very cheap on ebay:

Precision T3500:

https://www.ebay.com/itm/Dell-Precision-T3500-2-4GHz-Dual-Core-Xeon-X3503-8GB-DDR3-RAM-500GB-HDD-WIN10/172901256506?hash=item2841b7cd3a:g:7CIAAOSwArxZ0nbl 

https://www.ebay.com/itm/Dell-Precision-T3500-Xeon-E5520-Desktop-2-27GHz-250GB-4GB-Computer/282716856294?hash=item41d33cdfe6:g:MjcAAOSw7RdZ1Tc0 ($70)

https://www.ebay.com/itm/Dell-Precision-T3500-Xeon-W3505-2-53GHz-Dual-Core-6GB-250GB-HDD-8220/382249483651?hash=item58ffd83d83:g:NaAAAOSw9fNZgLmq ($80)

These systems are much more capable then your $40 optiplex another great idea would be to buy a precision laptop which would be a little bit pricey but it will be ready to go out of the box.

https://www.ebay.com/itm/Dell-Precision-M4600-Laptop-2-70GHz-i7-2620M-8GB-250GB-1777-Webcam-Touchscreen/292314420826?hash=item440f4c165a:g:bo8AAOSwUYNZ-fjb ($189)

The Precision's only real advantage over the Optis seems to be the Xeon CPU about 2x faster than Core Duo, which is negated if we spend $10 for a quad core upgrade.  If we compare apples to apples (8GB, HDD, W10), the Opti now costs $70 whereas the three Precisions you mention would cost $95, 115 and 95.  Furthermore, Optis are just more abundant out in the world.  This makes a difference if we need to scale up and provide them by the dozens.

The M4600 is a sweet setup (I know this because my son has the lesser M4400), completely out of our budget range.  You have to appreciate the criticality of cost.  Community college students tend toward poor.  For example, see  www.latimes.com/.../la-me-ln-homeless-community-college-20170628-story.html . LA Trade Tech is in a much poorer than average part of the city, so the situation must be even worse than the article suggests.  

Our computer provision project targets students who are not homeless, obviously, but have not been able to afford one and struggle to do assignments on the school's limited number of workstations, available for limited hours.  Taking some pressure off these computers makes them more available to students whose living situation is too precarious to accomodate a workstation of their own.

The T3500 is more than 8 to 10X faster than any Core 2 duo or Core 2 Quad Optiplex and can have Hex Cores and 24 Gigs of ram with 2 Video cards in Crossfire mode.   More storage, DDR3 Ram, Faster Multi Core Nelahem processors make them Light Years ahead of the Optiplex in All respects.  They have 2 X16 video slots and an X8 slot that can take a bootable SSD hard drive.  The 3500's are equivalent to 2009 to 2012 Mac Pro systems.  The Nelahem processors with 6 Hyperthreaded cores look like 8 cores for the quads and 12 cores for the Hex Core CPUs.  SLBVX 3.46 Ghz Hex Core Xeon X5690 is top end.

The 3400's are limited to Quad core Xtreme and 16 Gigs of ECC ram and also have the Dual X16 slots as well as the X8 raid card PCI -E Slot.

Both systems are much better due to being many times more capable, expandable and reliable.   The 3500 with Hex core procesor is EXACTLY the same Hardware as 2009 - 2012 DDR3 Mac Pro

http://barefeats.com/tube12.html

The FirePro D700s in the 2013 Mac Pro can be considered 'competitive' as a gaming platform but under OS X Mavericks. But if your gaming is done under Windows 8.1 (Boot Camp) in CrossFiremode, you will see a dramatic increase in the performance of some games.

Those of you 'retaining' your Mac Pro tower can rest assured that high-end GPUs keep it competitive when it comes to gaming. The same boost is available on the Mac Pro towers under Windows 7 and 8 if you have a pair of AMD GPUs jumped and CrossFire mode enabled.

I own both types of machines and can definitively say that When you have the optional Firewire card installed in the T3500 that the hardware is virtually indistinguishable from the Quad or Hex Core Mac pro.

The T3400 and T3500 are also certified to run Autocad, Maya, etc.

Quadro 600 cards are not expensive but the T3400 and T3500 can also take Quadro 6000's or even the Titan X cards.

https://www.amazon.com/PNY-DisplayPort-Professional-Graphics-VCQ600-PB/dp/B0046HUK3K

So as far as upgrade-ability and reliability and performance they beat ANY of the Optiplex models easily.

The hex core x5690 starts at $140 on Ebay and benchmarks at 9,019 passmarks, so that's 64 passmarks to the dollar.  The quad core q8200 sells for as little as $5.50 and scores 2,821 passmarks, so that's 513 passmarks to the dollar.  For a starving architecture student, the choice seems pretty clear!

I have to disagree entirely.  The low cost systems being recommended are much better and do not require upgrades,  I advise clients and co workers all the time on hardware and software.

Your $5 cost for windows Academic is not something that can be purchased or sold.  500 Gig hard drive,  Windows 10, 8 Gigs of ram under $100 is by far a much better and more long lasting "value".  If you include the longevity and reliability its no contest.

Have you looked into possibly talking to the Dell Foundation or Dell Financial Services for donation items?  Goodwill ReCompute would also be another avenue.

https://computersforlearning.gov/

Nearly Free, Computers for Students

Computers for Learning (CFL) doesn’t offer a lot of information, but we can tell you this:

   CFL is a federally funded nonprofit

   You can register for free computers by filling out an online application here

   Schools are only eligible if they can provide a National Center for Educational Statistics

(NCES) number issued by the U.S. Department of Education

If you have more specific questions, call (866) 472-9161.

Computers offered through Computers for Students aren’t free, they are cheap: Desktop computers cost $80 and laptops are $150.

Students can apply for discounted computers by completing this application form. Once they are reviewed and approved, a voucher will be mailed to the student. If students are located in the Arlington, Virginia area, they can pick up the system in person. If not, Computers for Students will deliver or ship at an extra fee.

Computer Recycling Center offers two free systems:

Sys # 1301nw: Core 2 Duo / Duo Core desktop, 1 GB memory, 160+ gig HDD.

Sys # 1304nw: Laptop, 1.0 GB memory, 80+ GB HDD, AC adaptor.

Requests for computers must be submitted on letterhead with the following information:

• The CRC system# of the computer you want
• The software programs you intend to run on the computer
• How you will use the computer in your program
• Who will benefit from this computer

Applicants will receive a response within 30 days. If approved, the applicant pays the cost of shipping.

Computers with Causes is slim on information, but applying for a free computer is easy. Simply complete the online application form and briefly explain your computer needs.

To qualify for a free computer from The On It Foundation applicants must:

Be in grades K-12

Receive a free or reduced school lunch

Attend a public school

Reside within the United States

If computers are not available, the applicant’s name will be placed on a waiting list. The student’s parent/guardian must write to The On It Foundation requesting a free computer. Information in the letter must provide the following:

• Student’s name, age, grade, school name, school address and school phone number
• Parent/guardian name, address, phone number
• Proof from the school (on its letterhead) that the student qualifies for free or reduced school lunch

I have to disagree entirely.  The low cost systems being recommended are much better and do not require upgrades,  I advise clients and co workers all the time on hardware and software. Your $5 cost for windows Academic is not something that can be purchased or sold.  500 Gig hard drive,  Windows 10, 8 Gigs of ram under $100 is by far a much better and more long lasting "value".  If you include the longevity and reliability its no contest.

True, I tried making a gaming rig out of a Dell Optiplex 780 Mini Tower and the build started with $70 but then I realized in order to get good performance out of it I would need to get better hardware which I did but, my build went from a $70 gaming PC to a $250+ build when I added stuff like better memory and a Nvidia GTX 1050ti. So while the Optiplex will cost way less, upgrades will bring the price back up to a Premium.

System Referenced: