Norie
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Graphics card for SFF Dell Optiplex
I'm looking for a graphics card for a SFF Dell Optiplex 790.
You have two limiting factors.
The ability of the 790’s power supply to deliver more than 35W power to the card slot
The limit of the case form factor and its poor cooling of expansion cards.
In a previous question I recommended either GeForce GT 240 or Radeon HD 2900 Pro
https://www.experts-exchange.com/questions/28052888/Dell-Optiplex-790-Video-Card-and-Power-Supply-Looking-to-Upgrade.html
Depends a lot on why you want to upgrade, bear in mind you’ll never make this into a games machine.
The USFF case and low profile cards are a real challenge. If you had the tower case your options could include Intel HD, Intel HD 2000, Radeon HD6350 or HD6450.
The ability of the 790’s power supply to deliver more than 35W power to the card slot
The limit of the case form factor and its poor cooling of expansion cards.
In a previous question I recommended either GeForce GT 240 or Radeon HD 2900 Pro
https://www.experts-exchange.com/questions/28052888/Dell-Optiplex-790-Video-Card-and-Power-Supply-Looking-to-Upgrade.html
Depends a lot on why you want to upgrade, bear in mind you’ll never make this into a games machine.
The USFF case and low profile cards are a real challenge. If you had the tower case your options could include Intel HD, Intel HD 2000, Radeon HD6350 or HD6450.
One of these https://www.amazon.com/GIGABYTE-GeForce-GV-N1030D5-2GL-Computer-Graphics/dp/B071DY2VJR
These come in at just over 30 watts. See https://www.tomshardware.com/reviews/nvidia-geforce-gt-1030-2gb,5110-9.html for a review.
If you do buy a GT 1030 make sure it has GDDR5.
You'll get to play a lot of older games with one of these.
These come in at just over 30 watts. See https://www.tomshardware.com/reviews/nvidia-geforce-gt-1030-2gb,5110-9.html for a review.
If you do buy a GT 1030 make sure it has GDDR5.
You'll get to play a lot of older games with one of these.
I have used Radeon 5450 and 6450 cards in 780s with good success but it pushes the power supply right up to the limit. However, since the supplied graphics in these units are Radeon 6350s I'm not sure that an add-in card will do much better. You might be able to get away with a Radeon 6750 if the disk drive is low power and the DVD drive is idle. The main issues, as stated above, are the power draw and the lack of support for PCIx video sockets.
The 780s were way underpowered at 240 watts and the 790s are no better. Attached below is an extract from an article I wrote but never published on that issue.
Tot up all the power draws in the system and you'll find that the power supply is being pushed near to the 80% level even by the standard equipment. An add-in card that pulls any significant power is asking a lot from that little power supply.
(header of article clipped)
The Crappy Power Supply
Now (discounting problem #3 below) the power supply in the 780 isn't really all that bad. I've seen worse - though not recently. However, this system was sold into the business market. Admittedly the low end of that market, but nonetheless in such systems one reasonably expects a decent power supply and this one just falls short of that mark.
I figure it would have cost about $5 more in manufacturing to have installed a decent power supply. That extra investment would have eliminated all the issues below.
TCPS: It's Underpowered
A 250 watt power supply was well under the standard of 350 watts even in 2010. This one isn't even 250 watts, it's 240.
The motherboard and BIOS support Core 2 Quad CPUs, but 780s generally shipped with Core 2 Duos. One reason is that the system is borderline hungry for power. Upgrading a Core 2 Duo E5400 (2.7 GHz, 65 watts) to a Core 2 Quad Q6600 (2.4 GHz, 105 watts) means that CPU power consumption goes from a third of the power supply to nearly half of it.
That doesn't leave much power left over for other components - the motherboard itself, the memory, the CD drive and the disk drive. And very little for an add-in GPU. Which brings us to ...
TCPS: It's Underconnected
It's pretty much "tough luck" as far as installing anything that uses Molex connectors. There aren't any.
Likewise, there's no installing a GPU that needs external power – not even the slightest amount of external power. There is no way to install anything requiring auxiliary GPU power. That restricts the selection of add-in GPUs to very basic units that can satisfy their power requirements from the PCI Express socket.
TCPS: It's Got Thermal Issues
This is the big one and I'm going to spend a little time on it because poor engineering annoys me, and from what I saw inside I think this problem is indeed poor engineering.
I took one system as a test unit, upgraded the E5400 CPU to Q6600, installed a modest Radeon 6750, brought up Windows 7, and started a burn-in using BOINC on all 4 CPUs plus the GPU. Task Manager showed all 4 CPUs at 100%. About 5 minutes later, hot air started floating out of the top of the power supply. 10 minutes later, the top of the supply was uncomfortably warm.
Checking the back of the supply, the hot air was just casually drifting out. So I closed the case and waited for the Dell CPU-case-motherboard one-fan-does-it-all fan to start pushing air out the power supply. Which it did not.
At this point the top of the power supply was too hot to touch for more than a few seconds. So I shut it all down, swore a bit and realized I'd have to shoehorn a fan into or onto the power supply, as no fan was visible from the back.
After pulling the supply out of the case and opening it up came the surprise.
This supply has a fan but does not use it.
The fan is located in the front of the supply, not the rear; it's a pusher configuration. Fine, it pushes instead of pulls, but why doesn't it use the fan?
Tracing the fan wires to the supply board, it developed that the fan was connected to a little area of "stuff" at the back. On closer inspection the "stuff" turned out to be something driving a transistor which presumably turned the fan on when the supply became hot. But it didn't.
At the back grille of the power supply (a) air was drifting out the top hot enough to cook a hot dog acceptably, but (b) no air was moving across the bottom, so (c) the probably-thermal-controlle
There were three chances to catch this problem, and all failed.
1. Someone, who surely knew the fan would not be running when the supply started to overheat, who surely knew hot air rises, placed the thermal sensor at the bottom of the power supply case where air is at least 20 degrees cooler when overheating begins.
2. A design review panel looked at this, says "Looks good" and approved the design.
3. This design was not tested in actual use, viz. installed in a running system, to see the real-world performance. It wouldn't have been found acceptable.
It was clear that the supply would become uncomfortably hot before the fan kicked on. "Uncomfortably hot" is never good for electronics, and particularly not for the wet-electrolyte filter capacitors which are a big part of a switching power supply.
Somewhere out there are people who deserve the item coming up next, and it is my humble joy to present it to them.
The 780s were way underpowered at 240 watts and the 790s are no better. Attached below is an extract from an article I wrote but never published on that issue.
Tot up all the power draws in the system and you'll find that the power supply is being pushed near to the 80% level even by the standard equipment. An add-in card that pulls any significant power is asking a lot from that little power supply.
(header of article clipped)
The Crappy Power Supply
Now (discounting problem #3 below) the power supply in the 780 isn't really all that bad. I've seen worse - though not recently. However, this system was sold into the business market. Admittedly the low end of that market, but nonetheless in such systems one reasonably expects a decent power supply and this one just falls short of that mark.
I figure it would have cost about $5 more in manufacturing to have installed a decent power supply. That extra investment would have eliminated all the issues below.
TCPS: It's Underpowered
A 250 watt power supply was well under the standard of 350 watts even in 2010. This one isn't even 250 watts, it's 240.
The motherboard and BIOS support Core 2 Quad CPUs, but 780s generally shipped with Core 2 Duos. One reason is that the system is borderline hungry for power. Upgrading a Core 2 Duo E5400 (2.7 GHz, 65 watts) to a Core 2 Quad Q6600 (2.4 GHz, 105 watts) means that CPU power consumption goes from a third of the power supply to nearly half of it.
That doesn't leave much power left over for other components - the motherboard itself, the memory, the CD drive and the disk drive. And very little for an add-in GPU. Which brings us to ...
TCPS: It's Underconnected
It's pretty much "tough luck" as far as installing anything that uses Molex connectors. There aren't any.
Likewise, there's no installing a GPU that needs external power – not even the slightest amount of external power. There is no way to install anything requiring auxiliary GPU power. That restricts the selection of add-in GPUs to very basic units that can satisfy their power requirements from the PCI Express socket.
TCPS: It's Got Thermal Issues
This is the big one and I'm going to spend a little time on it because poor engineering annoys me, and from what I saw inside I think this problem is indeed poor engineering.
I took one system as a test unit, upgraded the E5400 CPU to Q6600, installed a modest Radeon 6750, brought up Windows 7, and started a burn-in using BOINC on all 4 CPUs plus the GPU. Task Manager showed all 4 CPUs at 100%. About 5 minutes later, hot air started floating out of the top of the power supply. 10 minutes later, the top of the supply was uncomfortably warm.
Checking the back of the supply, the hot air was just casually drifting out. So I closed the case and waited for the Dell CPU-case-motherboard one-fan-does-it-all fan to start pushing air out the power supply. Which it did not.
At this point the top of the power supply was too hot to touch for more than a few seconds. So I shut it all down, swore a bit and realized I'd have to shoehorn a fan into or onto the power supply, as no fan was visible from the back.
After pulling the supply out of the case and opening it up came the surprise.
This supply has a fan but does not use it.
The fan is located in the front of the supply, not the rear; it's a pusher configuration. Fine, it pushes instead of pulls, but why doesn't it use the fan?
Tracing the fan wires to the supply board, it developed that the fan was connected to a little area of "stuff" at the back. On closer inspection the "stuff" turned out to be something driving a transistor which presumably turned the fan on when the supply became hot. But it didn't.
At the back grille of the power supply (a) air was drifting out the top hot enough to cook a hot dog acceptably, but (b) no air was moving across the bottom, so (c) the probably-thermal-controlle
There were three chances to catch this problem, and all failed.
1. Someone, who surely knew the fan would not be running when the supply started to overheat, who surely knew hot air rises, placed the thermal sensor at the bottom of the power supply case where air is at least 20 degrees cooler when overheating begins.
2. A design review panel looked at this, says "Looks good" and approved the design.
3. This design was not tested in actual use, viz. installed in a running system, to see the real-world performance. It wouldn't have been found acceptable.
It was clear that the supply would become uncomfortably hot before the fan kicked on. "Uncomfortably hot" is never good for electronics, and particularly not for the wet-electrolyte filter capacitors which are a big part of a switching power supply.
Somewhere out there are people who deserve the item coming up next, and it is my humble joy to present it to them.
ASKER CERTIFIED SOLUTION
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(Note that the power supplies in the 780 and the 790 are both 240 watt units, so the same power restrictions apply for a stock power supply. If the power supply is switched out, then anything can be installed as far as graphics.)
ASKER
Thanks for all the suggestions/advice.
Didn't realize it was so complicated, not had my own desktop PC for years.
It's actually a refurbished model so I think the first thing I need to do is have a look under the 'hood' to see what I'm actually dealing with.
Once I've done that I'll report back.:)
Didn't realize it was so complicated, not had my own desktop PC for years.
It's actually a refurbished model so I think the first thing I need to do is have a look under the 'hood' to see what I'm actually dealing with.
Once I've done that I'll report back.:)
ASKER
No.
Not a low profile card. That's what you need. Power consumption might be just OK. Appears to be 25 watts but would need to verify with Gigabyte on that point. But because it isn't a low profile card that point is moot.
Get a GT 1030 rather than a GT 730.
Not a low profile card. That's what you need. Power consumption might be just OK. Appears to be 25 watts but would need to verify with Gigabyte on that point. But because it isn't a low profile card that point is moot.
Get a GT 1030 rather than a GT 730.
ASKER
I did specify 'low profile' in the search, suppose I should look a bit closer at the result(s).:)
The one I initially mentioned is stated as needing 25W. Does it somehow not fit your needs?
ASKER
Not had a chance to check that out, will do later.
https://www.amazon.com/ZOTAC-GeForce-PCI-E2-0-Graphics-ZT-71301-20L/dp/B01AZ7W76W/ref=sr_1_3?s=pc&ie=UTF8&qid=1535746760&sr=1-3&keywords=low+profile
There are many others, too.