SFF GTX 750 ti, low profile, single (ish) slot mod

[Calibre41]

It's been many years since I messed about with a desktop PC. I just thought I'd get a thread started for a little project I'm embarking on.

I have a Dell Optiplex 3020 SFF which has a low profile, single slot PCIe slot. It mainly an office computer and I like the smart subtle appearance and size. It has an i5-4590 so it's no slouch, perfect for gaming, it just needs a little boost to GPU power. The only issue is, its very tight in there, tighter than it looks in images.

http://www.digitalwish.com/prod_images/3020_s3_full.jpg

** Do Not Hotlinkimages **


I currently have a low profile AMD 8570 1gb, it handles all my games, but it's FPS is dipping to undesirable levels in Battlefield 4 at 1080p (2.1MP), and its just acceptable enough to play online at 1680x1050 (1.8MP, about 85% of the pixels), but your not going to top the leader board!

The card is identical to an AMD R7 250 once MSI Afterburner has clocked it up 400mhz, it is very stable at these clocks and it makes almost no difference to temperatures, even after I've added 10degress to the set points on the fan profile

As the title suggests, I'm going to take a low profile GTX 750 ti and make it single slot-ish and I say ish, because I have a little extra room, so naturally, I want to maximise on it. I see no reason why things couldn't be larger or smaller if your wanting to do something similar but with a different space.

I found Gigabyte, KFA² and MSI cards readily available in the UK. I chose the MSI for 2 main and important reasons.

- Firstly, gigabyte were ruled out for fitting a dual slot backplate and stacking the DVI over the top. Lots of display ports, but no good to me!
- Secondly, I looked at the KFA² and MSI coolers, The MSI has a flat top, with 2 fans sitting on top, the KFA opts to sit a single fan in a machined recess giving it more fin area, but this doesn't suit the sort of mods I want to do, its not a problem, it would just be more work, and entail serious, no going back to standard modification. If I remove the fans from the MSI, I'll have a much lower profile, and just from looking at the images, it might just be enough to slot in place, without giving the cooler a hair cut.

Going fanless is clearly not going to work. So I plan to convert the MSI in to a mini blower style cooler. I'll 3D print a cover to totally enclose the stock fins which run front to back already. I'll try to direct the back end towards some vents in the back of the case so we're actually removing the heat, I'll even consider a side exhaust and slot the case if need be.

I'll have a dig around my junk box and see if I can find a centrifugal fan. I think I have a few dual slot 3850/70's, a single slot 3650 and a 4870x2 + a spare air cooler for a 4870x2 (which has 2 nice purecopper skieved fin blocks!!). I'll mount this fan anywhere it will fit, it might be at 90 degrees, it might be at 180degrees running along the back of the card, ducting round to the enlosed cooler on the front. It might be remote, and I'll try and use some standard flexi hose to connect it remotely (seem a bit far fetched, I should have room for a direct mount and theres probably more room right next to it)

So, we'll be combining a bit a of 3D printing and some good old scavenging to find a solution. If the cooler with the fans removed is still too tall, I have my own private machine shop in my garden which includes a CNC package, who doesn't?

I carefully cut the back out of the PCIe 1x slot that is above the 16x slot, and installed a 50w TDP card but it didn't work, it probably wasn't getting the power it needed. Why Dell didn't place the x16 slot on top I'll never know, there are 2 slots, it would have opened doors to dual slot cards if the user didnt want the PCIe 1x slot!!! - but no, they put it right next to the bloody PSU.....

On the side, I have a spare brand new 10w DDC and I've bought a cheap but low profile GPU waterblock with 43mm spacing (none of the big names make blocks this small that are low profile). I'm aiming to have the CPU and GPU watercooled, but its bloody tight in that case so take it with a pinch of salt. If I remove the CPU cooler, fit the lowest profile block I can find (GPU block so it has side port), that leaves me just enough room for a half thickness 120/140 fan and a radiator up to 35mm thick - this will leave me, 1mm clearance between the fan/radiator and the CPU block (depending on if I push or pull the fan).

It's all good fun.

 

[Calibre41]

Have you already tried the 750ti in there? I would be surprised if the slot actually provides the power needed, as in SFF OEM PCs they are normally limited to 35w or thereabouts.

No it should be here next week!

If that is the case, perhaps I'll be able to hard wire a bit of extra juice in to it - totally uncharted territory for me but I would guess looking online at a quick pinnout, add 12v to 1B, 2A&B, and 3A

 

[Calibre41]

I just found a single slot Sapphire 3650 (11127-02) which has a good size cooler (65TDP, vs the 750ti's 60w if my google search is correct)

It has 43mm hole spacing although I think TomsHardware has covered these, you have to drill out the mount holes which I'd rather not as I think I can do better with the stock cooler.

Worth knowing though for anyone else looking in to it. I'll offer up the cooler and see how it might look in terms of clearance etc.

 

[Calibre41]

As above, they are usually very low powered slots on SFF pcs like this.

Do you think I'd be able to bridge some extra power over to the 12v pins?

 

[Calibre41]

I'm just googling, the 8570 (standard Dell option) is 66w TDP if the first random source I've found is correct?

I've looked on AMD's site and they just list basic specs and features

 

[Calibre41]

Not something I'd attempt. Whilst the i5 is a great chip, gaming isn't what pc was designed for.

I can't disagree with that comment but this is "Overclockers" - I would have thought this is all about taking things beyond what they were designed for, and this is what I have, and I like it, the case is good and solid and knocks a lot of the fans whining noise out, everything is quick release, I can strip it down to the case with mobo and cpu+cooler without PSU, HDD, DVD, etc all by removing only 1 screw(to release the PSU)

I would love to see the real world FPS performance difference on something like battlefield 4 between something like an i5-4590 on a H81 chipset and a high end intel extreme machine of the same generation with the same RAM and GPU, I would guess, its only 5 to 10%? I could be very wrong, but I doubt it.

If the system is capable of running my games at just 1080, the project will have been a great success - exactly what I designed it for If I can make it as quiet at possible, bonus - I'll be chuffed to bits.

I've got a big liquid cooled lianli PC60 (Vintage I know) in the loft if I want to get something a bit more lively going!

 

[Calibre41]

We'll agree to disagree since this case is what I want

The only constraint I see is the PSU, and in today's low TDP market, that's no longer an issue, a 66w CPU flat out, combined in the same rail with a 65w GPU flat out isn't even close to half the total PSU Max, and only 2/3rd's of that rial (there are 2 14amp rails) - I've had significantly more power running through many of my laptops in the last 5 years, so from my perspective, this is going to be cool and quiet with a reasonably well balanced CPU/GPU combo.

The case also has excellent cooling characteristics and a strong well thought out flow, given its tiny volume the number of complete air changes per time period will be higher than that of a different case even though it only runs a small fan, I know this because I've watched it on my FLIR and I can continue to monitor and record temps and look for any potential air flow dead zones/hot spots

I feel technologies and TDP's have move on significantly in the last 6 or 7 years and running this setup, in this case, is a walk in the park, worst case scenario, I may have to get a new mobo which isn't a big drama as this thing is almost standard matx, I may just have to add/remove some mounts (they have likely secured the CPU cooler directly to threaded holes in the case from my experience of similar machines)

It's not like I'm trying to run a 120w CPU with a 200w GPU, this should be a well rounded build (he says as he jinx's the whole thing )

 

[Calibre41]

I have a sff 790 which I was wondering wether a LP 750 I have would work.

May have a play and see

Edit, someone has a 790 SFF and theyve got a 750ti in it, and have been running it for some time by the sounds of it!! http://en.community.dell.com/support-forums/desktop/f/3515/t/19657233

edit again, it looks like your x16 slot is first in line so you can fit a fit a standard cooler too, lucky bugger!!! I can't understand why the hell they but the x16 slot on mine right next to the bleeding PSU!



It could be well worth a look! Do you have any writing near the PCIe slot (some say MAX 30w TDP or something to that effect!)

In which case, the 750ti might not work, although you could try a hillbilly mod and solder some extra 12v wires to the appropriate 4 pins on the PCIe slot - totally untested, I don't know if this would work or know of anyone daft enough to have tried it, but this is what I'll be doing if I can't get it to work from stock!)

The top graphics option on the 790 is an R7 240 which is only a 30w TDP card. Mine has the previous gen 8570 in, which is a 60w board (apparently anyway! sources are few and far between for this odd model)

 

[Calibre41]

My low profile GTX 750ti finally arrived

As I suspected, it doesn't fit with the dual slot cooler, as my magical laser scanning eyes predicted, with the fans removed, its a dam near perfect fit!

Unfortunately, the fan mount holes are a bizzare shape, so the waterblock I've got won't fit, and I would guess, no off the shelf stuff is going to help me here. I wonder if the other brands have done the same to their LP 750ti's

My 4870x2 blower fan is much larger than I remembered, I'm going to leave it. The dual slot 3870 is even larger, and the single slot 3650 is as large in diameter. So I've got a 40x40x20 fan, which I presume is 12v (its out of a 12vdc-240vac inverter that died prematurely) It's a good size, and should provide good flow - I'm not sure about the noise but Scythe do some 40mm and 50mm fans so there's probably room for improvement/dual fans further down line.

Right, time to get the drawing board out and start designing this cooler

 

[Calibre41]

I'll obviously have to work on those images!

Preliminary testing went well, I sellotaped - yes, sellotaped the 40mm fan to the back of the cooler and all went well, temps were 85c ish during benchmarks but that's not what I was looking at, I just wanted to check it would work and the slot would provide enough power etc.

I've knocked up a rough 3D model to duct the 40mm fan to the cooler and enclose the fins. There's a slight obstruction so I couldn't get a great smooth transition from 40mm round to the approx 52x15mm rectangle cooler, it's just a mock up for now, I'll set my machine going tomorrow morning and it should be ready for testing by lunch time

 

[Calibre41]

kaku, your a legend thanks!

I'll get some more images prepped now - so ppl can see the sellotape

So, sellotape aside, the first prototype of the fan shroud is completed, assembled and installed! I've been running it for the last hour - its spot and fits beautifully, I just need to tweak a few dims (its currently touching the PSU and some holes I added for access are missing (I must have accidentally pressed Cntl+Z while modelling!)

Temps are spot on, it gets up to 80deg and the fan stays at 60% - the fan is silent if I recall upwards of 70 so I'll tweak the fan profile to see if I can get a better balance (it was 85-90% with temps around 88 with the sellotape cooler)

I'm also printing the second half of the shroud for those who've noticed its not as long as it should be..... I printed the first bit stood vertically on the 40mm fans mount face and as my new miniature machine can only print 100mm high I had to chop the end off. - I doubt this extra bit will make much difference to temps, the GPU is enclosed and the heat spreading base ends exactly where the current shroud ends so there won't be much heat getting carried to the remaining 45mm of cooling fins!!! (bits of surface mounted components are in the way, it would have been to much cost to machine holes and clearances for them all - I would if I made one from scratch but that's just me)

So, check back in an hour for an photo update and Unigine Valley 1.0 benchmark results, temps and fan speeds!

 

[Calibre41]

SO, V1 1/2 refers to Version 1 (half cooler, ie within the 100mm height of my printer)

Unigine Valley Benchmark 1.0 Extreme (windowed, 1600x900, Ultra, 8xAA, D3D11) i5-4590 3292MHz x4

FPS Score MIN MAX temp fan
V1 1/2 run1 27.3 1144 16.1 48.6 80 60
V1 1/2 run2 26.7 1119 16.3 47.7 80 60 Case Closed
V1 1/2 run3 26.6 1112 16.1 47.5 80 60 Case Closed

So, pretty consistent. Before I started the 1st run I left it looping for 5 minutes or more to get the temps up. From cold GPUz was reporting 115-120% TDP, and the boost clocks were flying, as the temps got up to 80, the boost diminished and it settled down to about +50mhz over stock and about 85% TDP - still, much better than throttling!

Pics..... (I will upload one to test size, then roll more out, these have been uploaded from the Google ios app, so its full res, I reduced the others but I can't seem to do that directly through the app or online afterwards)











and PING, the cooler extension is done, its currently cooling and I'll fit it in 5 minutes once I can handle it! I don't think it will help temperatures much, it may even make it slightly worse, so its a balancing act between cooling the GPU and kicking the heat out the back. If i leave it as is, it may build up heat over time and get hotter and hotter, but I could suffer a degree or 2 loss up front, if it means long term, its kicking enough out the back of the case to maintain stable temps inside.

 

[Calibre41]

Sorry, I promised sellotape - here it was

As I said, this was just a quick knock together to check it would actually handle the TDP of this card etc. and make sure the effort designing and prototyping a cooler was worth it.

 

[Calibre41]

Ok, so its as quick as that (10 minutes), shut down, remove GPU (remove PC from top of printer!) remove cooler extension, apply super glue, fix in place, photo, reinstall, reboot, google apps already uploaded the images!

This is what I call, ultra RAPID prototyping!!! If your paying attention to when I posted all these updates, its all done in about 24hrs so far (minus 12hrs at work, and 7 sleeping)


....... here she is.

 

[Calibre41]

Benchmarks incoming, I'll update this post but right away, she's idling at 41, and it was mid 30's before (could have just been residual heat in the case as its been benching continuously in the background the whole time I've been posting/designing and updating my excel results etc.

Update, I made some extra notes on core speed and voltage, it seems to get higher and higher (maybe case temps are dropping slowly from the last round of benches without the extension)

V1 Full refers to Version 1 (full cooler, ie within the extra bit stuck on!)

Unigine Valley Benchmark 1.0 Extreme (windowed, 1600x900, Ultra, 8xAA, D3D11) i5-4590 3292MHz x4

FPS Score MIN MAX temp fan
v1 full run1 26.7 1118 15.4 47.9 80 60 Case Closed 1045-1070mhz boost 1.062-1.087vcore
v1 full run2 26.8 1122 15.9 47.8 80 60 Case Closed 1058-1070mhz boost 1.075-1.087
v1 full run3 26.8 1121 16.1 47.5 80 60 Case Closed 1058-1097mhz boost 1.075-1.100

So, it's all looking good, I'm going to run it for a while now and get some hours on this card - enough playing with it, time to play on it! (actually after one more bench with 100% fan.......)

 

[Calibre41]

So, with fans on full, and given plenty of time to get up to temperature and settled...... it runs at 80c still. This is obviously just the temp that is being targeted by the boost. Core voltage and boost speeds were all much higher than previously. This tells me that if I can get more airflow, it will run faster - so I'll have to see about trying a 50mm fan, or dual 40's or perhaps just getting a branded fan (although the one that's in is actually very nice, with nicely designed blades, its very very quiet and produces a good solid pressure - shame theres no brand on it at all!)

I did progressively get a lower and lower score, so this isn't completely sustainable during 100% continuous load.

It actually ran a bit quicker, and was generally benching better all over. I had the intake fan, CPU fan and GPU fan all on 100%.
FPS Score MIN MAX temp fan
v1 full run1 case/cpu/gpu fans 100% 28.1 1174 16.5 50.9 80 100 Case Closed 1125-1150mhz boost 1.168-1.193vcore
v1 full run1 case/cpu/gpu fans 100% 28 1172 17.1 49.7 81 100 Case Closed 1150-1137mhz boost 1.168-1.193
v1 full run1 case/cpu/gpu fans 100% 27.9 1169 16.5 50 80 100 Case Closed 1136-1150mhz boost 1.168-1.193

 

[Calibre41]

I could see the new image links weren't working when I logged on from another PC, hopefully its sorted but I don't know what I'm doing here!

Can anyone recommend a free image host, google doesn't seem to be working out and my 10+ year old imageshack account turned out not to be "free forever" lol

 

[Calibre41]

imgur.com is completely free

Thanks I've just created an account

 

[Calibre41]

kaku, there is actually a tiny vented area its less that 1/2 the width of an actual slot - so the air being ducted down there is actually getting vented out the back of the case!

I've got a pair of Yate Loon 50x20 blowers, and knocked up a cooler design last night, its printing now although it may fail as its tricky to print - time will tell. I'm at work, the Robox it printing it at home - I'm thinking of getting an IP cam so I can keep an eye on it - I might put a request in to CEL (the manufacturer) that they add IP camera and remote kill switches to the software (they've already added GoPro compatibility so the machine moves out the way every so often, takes a frame for the time elapse and then continues printing )

All links updated to imgur, hopefully this is more reliable.

 

[Calibre41]

Just dropping by to say what a cool little project this is! Thoroughly enjoying your updates

Thanks very much, its nice to know its worthwhile posting

So, it printed, its bloody rough, but it printed. I'm going to have to work on making the design more suitable for a FFF printer but for now, results are looking good. Temperature wise, the fan profile is still targeting 60% and 80°C but clocks and core voltage are up on the V1 design. The fan was even backing off a little at times - its obviously providing a bit more oomph than that 40x20.

FPS Score MIN MAX temp fan
v3 27.5 1149 16.1 48.8 80 57-60 Case Closed 1071-1097mhz boost 1.100-1.125vcore
v3 27.4 1148 15.9 48.9 80 57-60 Case Closed 1071-1097mhz boost 1.100-1.112vcore
v3 27.4 1149 16.9 49.3 80 57-60 Case Closed 1071-1097mhz boost 1.087-1.112vcore

Kaku, here are the little vents between the card and the PSU - this is why my title says single slot "ish" as I have a tiny bit of extra head room, but no doubt most cases do otherwise face mounted fans would be blocked! - It kicks quite a lot of heat out of those holes and its something I can improve on by opening up the holes in to a single slot and/or sealing the cooler better so it has more pressure to push out the heat and less heat leaking back in to the case.



And here's version 3 with the 50x20 yate loon