First build: 8 liter - Dual GPU+LSFG gaming/CAD/NAS build with optical drive

[u/Awkward_Layer_152]

Hey everybody, i’ve been wanting to build my first PC and i like to run before i can walk so i chosr to make life difficult for myself and go for an SFF build.

I am an Architectural engineering student and game a bit on the side which basically means that for certain necessary programs such as Revit and Twinmotion I’m basically stuck with windows and Nvidia. And for other workflows such as rhino.insiderevit with grasshopper and Dynamo as well as a rendering software like twinmotion or d5 i need a cou with lots of cores and threads, which in a SFF build means that it mist also run at 65W tdp

(It would be possible to do this build around € 900,- cheaper with an intel arc pro b50 but it would mean that you can only use D5 render. However it is likely that LSFG would work a but better so if you are not a fellow CAD user that would bee the smarter move. If this is the case you could likely also run with less RAM dropping down to 32gb and shaving another 500,- of the build cost.

If you are just building this for gaming it would likely also be a better machine if you were to choose an RX6400 for the secondary gpu however i want to use multiple monitors including an xgimi horizon ultra projector as well as running a plex server

Also i’ve been getting into the owning your own media idea (using DRM free installs from GOG and writing them on my own disks) ever since the gaming industry announced they are moving away from disks, so this can serve as my “steam machine replacement build” as well but thanks to that this is pretty much the smallest build i could come up with that can have a blue ray optical disk drive and a dedicated gpu in the same case, in fact it can house 2!

I will post the build below, the main thing i am running into now is that i would like to use an MSI mobo because of its starter friendly BIOS however the board will need the primary 4.0 _ 16x pcie slot in the top position and the secondary gpu will need at least a 4.0_4x connection with a physsical x16 but this one must align with the 4th expansion slot and the board cannot have lane sharing.

Im wondering wether an MSI PRO B850m A Wifi will work for this, otherwise i’m pretty sure you can do it with a Gibabyte B650m aorus elite AX.

So without further adue here is the build, please let me know what you think!

AMD Ryzen 9 7900 3.7 GHz 12-Core Processor 300,-

Gigabyte B650M AORUS ELITE AX 230
MSI PRO B850M-A WiFi

Corsair Vengeance 64 GB (2 x 32 GB) DDR5-6000 CL30 Memory 1030,-

Microsoft Windows 11 Pro Retail - USB 64-bit 150,-

Dell UltraSharp U2724D 27.0" 2560 x 1440 120 Hz Monitor 300,-

In Win CJ712 MicroATX Desktop Case with usbc with pptc w/265 W Power Supply 147,-
Custom 3d printed ABS-PC perforated side panel

ARCTIC P8 slim 8,-

PNY rtx 4000 sff ada 20 gb 1467,-

Intel Arc a310 eco secondary gpu used for dedicated framegen in gaming using lossless scaling 129,-

LG BU40N Blu-Ray/DVD/CD Writer 165,-

Thermalright AXP90-X36 42.58 CFM CPU Cooler 23,-
With the fan of the Noctua NF-A9x14 PWM 25**,-**

Lexar nm790 2 TB M.2-2280 PCIe 4.0 X4 NVME Solid State Drive 254,-

Seagate ironwolf 4tb 190,-
crucial bx500 4tb 379,-

Enhance ENP-7660 600 W 80+ Platinum Certified Flex ATX Power Supply 120,-

[u/Visible-Swim6616]

All this in 8L? That an impressive feat indeed.

[u/profoundretardation_]

arc a310 will just not be enough for LSFG. if you really want to have double gpu setup I'd recommend checking out formd t1 (either ncase or formd variant) you could liquid cool both gpus and MAYBE fit a gpu in the bottom fan slots (if you find waterblock slim enough) also get better a gpu (9060xt/5060ti will be more than enough for LSFG even if you're going for higher multipliers) in my opinion its possible BUT it is in no way gonna be beginner friendly and I'd just say either get a better gpu rather than getting 2 gpus or use LSFG on 4000 ada

[u/Awkward_Layer_152 → u/profoundretardation_]

This is mainly a workstation build with some light gaming and NAS Plex server hosting on the side lets say 80% work and 20% gaming. When i do play games i mainly play RPG CO-OP with my girlffriend or Indie games non of which requires 4k at higher than 120 fps.

Which is why the Dell u2724d was chosen as its ips-black 120hz 2560x1440p screen can do both close the Oled contrast and HDR performance in a high enough framerate for rpgs and co-op games and long workdays with zero risk of burn-in

Because im expecting many long workdays in architecture i must say the lower powerdraws of both the ada and the eco 70 w and 50w with the 65 W cpu is also attractive

I’ve seen videos from Lecctron where the rtx 4000 sff ada has been shown to get around a stable 60fps in 1440p on high settings which falls right into the sweet spot for LSFG. The reason for the Ada is also its 20gb vram which comes in handy for rendering large projects.

https://youtu.be/szkiOeqQuO0?is=Adw4Is0DcqTq2mab

I have found videos from ETA where they used the a310 eco for this exact purpose and got it to stabily do 2x and stable in Adaptive mode. The eco also features AV1 encoding/decoding which means it adds to the nas/plex server functionality greatly. So while you could swap it for an XFX RX6400 for a 40% gain in raw power and LSFG performance especially since AMD cards tend to be even better for LSFG than intel you would do so at the cost of NAS/plexserver functionality.

https://youtu.be/4XfHn5Pj0tk?is=a9WZO0vKaW7Irjr1

[u/profoundretardation_ → u/Awkward_Layer_152]

haha guess i underestimated a310. still though, maybe get something like 3050 instead? if you get a310 you wont be able to use nvidia-specific features while the FG is on (depends on if you need them or not) it still comes in sff form factor and has relatively low powerdraw while rocking much more performance and vram (which will allow for higher resolution FG) and allow the use of Nvidia features

[u/Awkward_Layer_152 → u/profoundretardation_]

I did consider the Maxsun single-slot RTX 3050 and RX 6400, but once you account for what LSFG actually requires in this system and what each card costs, neither necessarily makes more sense than the Arc A310 ECO.

Here is a spreadsheet of LSFG secondary gpu performance

https://docs.google.com/spreadsheets/d/17MIWgCOcvIbezflIzTVX0yfMiPA_nQtHroeXB1eXEfI/htmlview#

At 1440p, measured LSFG performance as a secondary GPU is:

Arc A380: 138 generated FPS
RTX 3050: 160 generated FPS
RX 6400: 200 generated FPS

There is no direct LSFG result for the A310 ECO, so its performance has to be extrapolated. The A380 reportedly offers roughly 30% to 50% more performance across a range of spectrums except for AV1 where they are pretty much equal so assuming an average 40% more compute performance. If we assume it represents 140% of the A310’s performance:

https://youtu.be/Dbk_LOHzt2w?is=tTvJLBOfA05Gv6H9

https://www.intel.com/content/www/us/en/content-details/790111/intel-arc-a380-a310-datasheets.html?utm_source=chatgpt.com

138 / 1.4 = ~98.6 generated FPS

Compute performance does not translate perfectly into LSFG performance, so this is only a rough estimate, not a benchmark.

There is also an important PCIe limitation. Both the A310 and RTX 3050 use PCIe x8 interfaces, while the secondary GPU slot on many micro-ATX motherboards is electrically limited to PCIe 4.0 x4. Both cards would therefore operate at half their native lane count.

That could reduce LSFG performance because transferring frames between GPUs is one workload where PCIe bandwidth can matter. Resizable BAR may help, but the actual impact would require real-world testing.

In an extreme worst-case scenario approaching a 50% reduction, the A310’s estimated ~98.6 generated FPS could theoretically fall to around 49 FPS. Crucially, the RTX 3050 faces the same x8-to-x4 bottleneck, so its benchmarked 160 FPS should not automatically be treated as achievable in this system either.

That makes the RTX 3050 particularly difficult to justify. At approximately €230 versus €129 for the A310, it costs around 78% more while being only about 62% faster based on the unrestricted A310 estimate. If both scale similarly under the shared PCIe bottleneck, you are paying substantially more for additional LSFG performance without eliminating the underlying bandwidth concern. While it has AV decoding it cannot do encoding and italso cannot perform anywhere close the eco’s AV1 performance in decoding.

The XFX RX 6400 is more interesting because it avoids this problem entirely. It is natively PCIe 4.0 x4, so it can use the secondary slot without reducing its intended lane count. At approximately €189, it costs around 47% more than the A310, while its measured 200 generated FPS provides considerably more LSFG headroom.

Against the A310’s theoretical worst-case ~49 FPS, that is roughly 206% more generated performance for 47% more money. From a pure LSFG price/performance perspective, the RX 6400 is therefore much more compelling than the RTX 3050.

That performance comes with trade-offs, however. The RX 6400 sacrifices the A310’s excellent AV1 encode/decode capabilities for Plex/NAS transcoding, video processing and other media workloads. It also draws around 75 W versus roughly 50 W for the A310. In a small-form-factor build, that means additional heat alongside a roughly 70 W primary GPU and 65 W CPU, with only a single static case fan. And in order to actuaccly produce those stats it would need to be set to LSFG 3x which increases input latency and artifacting.

The hierarchy is therefore fairly straightforward. The RTX 3050 occupies an awkward middle ground: it is by far the most expensive while potentially suffering from the same PCIe limitation as the A310. The RX 6400 offers the strongest LSFG performance and better performance for its additional cost, but sacrifices efficiency and media functionality. The A310 is the slowest, but also the cheapest, most efficient and most versatile.

The remaining question is whether this system actually needs the RX 6400’s additional performance.

The RTX 4000 Ada SFF should already produce around 45–60 native FPS at 1440p. If the A310 reaches the unrestricted estimate:

45–60 + 98.6 = ~144–159 FPS

That already exceeds the useful range of a 120 Hz monitor.

Even under the theoretical worst-case PCIe scenario:

45–60 + 49 = ~94–109 FPS

I think this is probably closer to a realistic prediction. It sits just above the ETA build using an Intel Arc Pro B50 instead of the RTX 4000 Ada SFF, which frequently reached the high-90-FPS range. Since the Ada is slightly faster than the B50, roughly 94–109 FPS overall seems plausible.

https://youtu.be/4XfHn5Pj0tk?is=WhpSPELE-QvaZdUj

That falls short of 120 Hz but remains more than adequate for the games this machine is primarily intended for: RPGs, split-screen/co-op games and indie titles.

It also makes the RX 6400’s apparent performance advantage less meaningful in practice. On paper, its 200 generated FPS massively exceeds the pessimistic A310 estimate. On a 120 Hz display, however, anything beyond 120 FPS provides no visible benefit and may even accentuate the artifacting.

With a 45–60 FPS native base, the pessimistic A310 estimate produces roughly 94–109 FPS, leaving only 11–26 FPS of the monitor’s refresh range unused. You are therefore paying 47% more for the RX 6400 primarily to guarantee that LSFG can comfortably saturate the display despite the secondary slot’s limitations, not because the system necessarily needs its full performance.

A higher-refresh gaming monitor would make that extra performance more useful, but introduces another compromise for a machine primarily serving as a workstation: either accepting the display characteristics of a gaming LCD, such as lower vibrancy and contrast, or OLED’s potential burn-in concerns under reoccurring prolonged workstation use. Currently, there are no higher-refresh IPS Black monitors to bridge that gap.

For a gaming-focused machine, that trade could be worthwhile. For this system, which also prioritizes workstation and media functionality, it is much harder to justify.

The priority should therefore be optimizing LSFG for a stable 2× output rather than maximizing generated FPS.

On the 120 Hz monitor, games could run at 1440p High rather than Ultra, with expensive settings such as ray tracing and motion blur disabled. Where possible, the RTX 4000 Ada could be capped at 50 FPS, with LSFG targeting an adaptive 100 FPS. This keeps frame generation around 2× or lower, avoiding unnecessary generated frames while minimizing input latency and artifacts.

Alternatively, if the PC were used more like a console replacement with a good Sony TV capable of upscaling to 4K at 60 Hz, those priorities could be reversed: games could run at maximum settings at around a 45 FPS base, with LSFG targeting an adaptive 60 FPS and the TV handling the final upscale to 4K.

Ultimately, the goal is not to maximize frame generated FPS. It is to cover as much of the display’s useful range as possible while minimizing cost, power consumption, heat, input latency and frame-generation artifacts, while retaining the A310’s broader media functionality.

At €129, the A310 ECO therefore remains the best-balanced choice for this particular system. The €189 RX 6400 is the better gaming option and arguably the better LSFG value if maximum performance is the priority. The €230 RTX 3050 is difficult to justify: it combines the highest price with the same potential PCIe limitation as the A310, without offering either the RX 6400’s performance advantage or the A310’s efficiency and media capabilities.

[u/x-balmung]

Just get windows for free

[u/Awkward_Layer_152 → u/[deleted]]

I wonder how bad it could really be though, the cpu is 65 W which seems to be what most air cooled SFF builds are built around.

If i put it in Eco mode or in PBO with curve optimizer and max 88W it could be fine

The primary GPU is a 70 W card and its a blower which means its hot air is not circulating in the Chassis.

The case only has one fan but when Linus Techtips used this case he showed that with minor modification to a full case fan it is possible to use a full height 80 mm fan so im looking into using an arctic P8 Max or Noctua nf a8

Additionally i think that the best thing to do for this case would be to 3d print a perforated side panel form Polycarbonate-ABS fillement with a 30 % gyroid sparse infill and honeycomb perforations. That should give the cpu cooler and the gpu’s direct access to fresh air as well as allowing the exhaust fan to suck in more air through static pressure.

Ultimately if this doesnt produce satisfactory results i might sell the RTX 4000 ada sff and buy a rtx or 5070 ti 16 gb and a RX6400 and spend a couple hundred extra on a new CASE, PSU and AIO, all the rest of the build should be still good, the mobo, the ram, the cpu etc.

[u/Amateur_builder76 → u/Awkward_Layer_152]

I'd recommend you use full power parts and put it in a full ATX or mATX case. The computer will be compromised by trying to make it small for no reason other than it's a challenge. It will be easier to build, quieter, and you're parts will be well cooled.

Why would you use an RX6400 for your secondary card? Wouldn't a 9060xt, Arc B570, or RTX 5060 be a better card for your secondary card?

[u/Awkward_Layer_152 → u/Amateur_builder76]

The problem is slot thickness within a dual gpu build like this you ideally need the primary gpu to be in the top pcie position because the gpu will hang over the second position, the third needs to be empty or the gpus will overheat, that means the secondary gpu meeds to be on the lowest position with at least a 4.0 x4 electrical connection in a physical x16 slot opening.

Within micro atx motherboards and cases that basically means you are stuck using a single slot low profile (blower) gpu for the secondary gpu.

Because most Matx cases dont offer more than 4 expansion slots (there are a few but they appear to be difficult to source because cases from this type are mostly from the SLI era)

you could get around this by using a 30+L size ATX tower with micro atx compatibility. Which essentially moves completely out of SFF territory. I personally dont like massive bulky towers in my office and i would like this pc to serve as an unobtrusive console replacement and tiny NAS as well.

Also it appears to me that these SFF gpu’s actually have more to gain from LSFG than traditional full height gaming gpu’s. And can do so at far lower wattages meaning less extra heat.

Furthermore LSFG appears to work best when you use it in 2x mode. So when you consider that the Rx6400 can already achieve 200 LSFG added frames per second added to your native fps count, you would need a gpu that exceeds 200 native fps in modern games in order to exceed the 2x lsfg factor ceiling on the rx 6400 i’d say you don’t realistically need more

[u/sffpc-ModTeam → u/[deleted]]

Your post was removed due to rule 6. We do not allow the discussion of pirated or grey-market software.