Question Does the GTX 750 Ti work in this Dell Optiplex?

Apr 11, 2019
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I'm planning on buying this Dell Optiplex and I want to put an ASUS GTX 750 Ti inside. Will it fit and be compatible? Will it also be able to use the stock power supply? I'm not tech savvy so I'm pretty confused with this 6 pin and 8 pin stuff. All I know is that the GPU has a 6 pin PCIe (if that's what it's called). I know it's pretty outdated to use a 750 Ti in 2019 but this is just a cheap budget build for medium gaming.
Thanks in advance.
 

PC Tailor

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According to the 390 Technical Guide here - the motherboard does have a PCIe x16 slot for the 750 Ti to plug into.

However it also shows that it only really offers a 240 to 260W power supply, and Dell off the shelf computer PSUs are (from my experience) are notoriously bad quality. That and really you should have 300W for the 750Ti despite it being very power efficient for the performance.

So technically yes it's compatible, but the stock PSU would hold me back from throwing a dedicated GPU in it.
 

King_V

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First, I strongly suspect that no variant of the OptiPlex has the 6-pin connector, so, if your video card needs the 6-pin connector (a little surprising on a 750Ti, but I guess some variants of the 750Ti might require the connector), then you're probably out of luck. I could be wrong about the PSUs not having that connector, but I'm FAIRLY sure they don't.

That aside, if your GPU does NOT require the connector, I can say this:

Having used an Inspiron 3647 Small Desktop (Haswell era) with a 55W card and a 54W CPU, on a 220W PSU (216W max on 12V rail) I'd say that it SHOULD work. My son ran this for well over a year gaming with no trouble.

From that document @PC Tailor linked to, even the worst-case Small Form Factor has 17A on the 12V rail, thus 204W available.

Seems like this machine runs Skylake CPUs, so, as long as you run a non-K CPU, you're looking at a max of 65W for the CPU, and 60W for the 750Ti. That's 135W if running maxed out, leaving 69W for everything else.

That's pushing things really close. If you're running a lower-powered CPU, it gives you a little more headroom.

The desktop variant is 17.8A on the 12V rail, thus giving you slightly more headroom (9.6W extra), for a total of 213.6W on the 12V rail. The mini-tower version gives two rails, with on-paper 312W total, but the max limit for both 12V rails combined is 240W according to the document. That 240W gives you even more headroom.

I'm saying all this stuff with the different variations because I can't see the ebay link at the moment, so I don't know if you're looking at the SFF, Desktop, or Mini-Tower version.

My understanding is that, in the past several years, Dell's PSUs have gotten much better in quality. I've had no trouble with them (3 different XPS Towers with the standard 460W PSUs, and that 3647 with the 220W PSU) even when maybe running a bit more power-hungry of a video card than most people might assume should work.
 
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PC Tailor

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Agreed with above really. The 750 Ti is a brilliant power efficient card, but the Dell PSUs listed don't quite meet the needs IMO.

a little surprising on a 750Ti, but I guess some variants of the 750Ti might require the connector
I'm yet to encounter a 750Ti that does require additional power outside of the PCIe - being as it only draws 60W, I suspect it will always be sufficient with just the PCIe slot power (but I'd be interested to see a variant that does!).

I've had no trouble with them (3 different XPS Towers with the standard 460W PSUs, and that 3647 with the 220W PSU)
Agreed that I have also run multiple systems on newer and older Dell PSUs and have one as a tester unit myself, yet I've equally seen a lot of people effectively fry their systems if it does go bang. Doesn't happen often, but happens, I would say my suspicion is less about the power they deliver, but more about the safety features they have in extreme circumstances. But I could be wrong!
 
Apr 11, 2019
6
1
15
According to the 390 Technical Guide here - the motherboard does have a PCIe x16 slot for the 750 Ti to plug into.

However it also shows that it only really offers a 240 to 260W power supply, and Dell off the shelf computer PSUs are (from my experience) are notoriously bad quality. That and really you should have 300W for the 750Ti despite it being very power efficient for the performance.

So technically yes it's compatible, but the stock PSU would hold me back from throwing a dedicated GPU in it.
Thank you for this. I've decided to get this PSU as it will be better for me to upgrade the GPU in later months or even years. A friend told me it has x2 8 pin connectors and a 6 pin connector in one of the 8 pins (bits hanging off he said which makes it a 6 pin). Stupid question sorry but is this PSU compatible with the Dell PC? Can it plug into everything well like the motherboard and such? Thanks again for your help!
 

King_V

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Agreed that I have also run multiple systems on newer and older Dell PSUs and have one as a tester unit myself, yet I've equally seen a lot of people effectively fry their systems if it does go bang. Doesn't happen often, but happens, I would say my suspicion is less about the power they deliver, but more about the safety features they have in extreme circumstances. But I could be wrong!

Interestingly, these days, at least with the 460W PSU they provide in the XPS towers, Dell explicitly states that they will handle video cards up to 225W. Considering that they have to provide the warranty for this, I don't think that's a gamble they would take if they weren't confident in it, much less any potential liability if they go out in a literal blaze of glory. :eek:
 

King_V

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Thank you for this. I've decided to get this PSU as it will be better for me to upgrade the GPU in later months or even years. A friend told me it has x2 8 pin connectors and a 6 pin connector in one of the 8 pins (bits hanging off he said which makes it a 6 pin). Stupid question sorry but is this PSU compatible with the Dell PC? Can it plug into everything well like the motherboard and such? Thanks again for your help!

Hmm, I thought some of the Dell systems like that used a proprietary connector for the motherboard, but a quick Google image search seems to indicate the Optiplex 390 uses a standard 24-pin MB connector, which is good.

So, you can use the PSU you linked to. However, the EVGA White aren't considered good quality, at least according to this thread. I tend to recommend Seasonic, but they are pricier.

As to the 6/8 pin issue, yeah, to make them a little more universal, a lot of PSUs come with what's called a 6+2 connector. It's basically an 8-pin PCIe connector, but where the last 2 pins at the end can separate so that you can use the same wires for a video card regardless of whether it needs 6-pin connectors, or 8-pin.

Here's what they look like - in this case, it has two of those 6+2 pin connectors.

dual62pin.jpg
 
Apr 11, 2019
6
1
15
Hmm, I thought some of the Dell systems like that used a proprietary connector for the motherboard, but a quick Google image search seems to indicate the Optiplex 390 uses a standard 24-pin MB connector, which is good.

As to the 6/8 pin issue, yeah, to make them a little more universal, a lot of PSUs come with what's called a 6+2 connector. It's basically an 8-pin PCIe connector, but where the last 2 pins at the end can separate so that you can use the same wires for a video card regardless of whether it needs 6-pin connectors, or 8-pin.

Here's what they look like - in this case, it has two of those 6+2 pin connectors.

dual62pin.jpg
Wow that's really helpful. So are you basically saying that the GTX 750 Ti, Dell Optiplex 390 and the PSU I'm going to buy are all compatible?
 

King_V

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Should be - if you are getting the MiniTower version, I'm fairly (but NOT definitely) sure that uses a normal ATX power supply. I can't see the link to Ebay, so I don't know which form-factor of OptiPlex you're getting.

The smaller ones typically can't even fit a normal ATX power supply, and have some weird shape of their own, which are basically a pain and don't have upgrade options at all.
 
Apr 11, 2019
6
1
15
Should be - if you are getting the MiniTower version, I'm fairly (but NOT definitely) sure that uses a normal ATX power supply. I can't see the link to Ebay, so I don't know which form-factor of OptiPlex you're getting.

The smaller ones typically can't even fit a normal ATX power supply, and have some weird shape of their own, which are basically a pain and don't have upgrade options at all.
Yeah it's a mini tower so I think it'll fit. Thanks for all your help!
 
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