Pci gpu passthrough idiots guide?

Look online if someone near you want to get rid of old computers. Often you find complete working computers based on early i5/i7s CPUs for as less than 50€.
 
will anything running i5 offer vt-d and gpu passthrough? Anyone offer advice on a system so i dont get the wrong thing?
 
Would a Dell Optiplex 3040 have the means? with i5 ? says intel H110 chipset? maybe i can find a guide on here for a newbie build or purchase?
 
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My advice for budget systems would be to look for used systems with AMD A-series processors. These generally supported VT-d and IOMMU although there is still a bit of a crap-shoot about how well the motherboard bios supports IOMMU (ASROCK, and ASUS were generally quite good if IRC) and the processors have on-board graphics so you could re-use your existing graphics card. Then max out ram and fast storage as far as your budget allows.
 
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Ran dmesg | grep -e DMAR -e IOMMU and it confirms that VT-d is enabled in the bios....so must just be the damn g33 chipset stopping it. So annoying.
 
Ran dmesg | grep -e DMAR -e IOMMU and it confirms that VT-d is enabled in the bios....so must just be the damn g33 chipset stopping it. So annoying.
Still no IOMMU groups? As I asked before, maybe you can run this: for d in /sys/kernel/iommu_groups/*/devices/*; do n=${d#*/iommu_groups/*}; n=${n%%/*}; printf 'IOMMU group %s ' "$n"; lspci -nns "${d##*/}"; done. That will also give information about the motherboard and chipset.
 
Still no IOMMU groups? As I asked before, maybe you can run this: for d in /sys/kernel/iommu_groups/*/devices/*; do n=${d#*/iommu_groups/*}; n=${n%%/*}; printf 'IOMMU group %s ' "$n"; lspci -nns "${d##*/}"; done. That will also give information about the motherboard and chipset.
IOMMU group * 00:00.0 Host bridge [0600]: Intel Corporation 82G33/G31/P35/P31 Express DRAM Controller [8086:29c0] (rev 02)
00:01.0 PCI bridge [0604]: Intel Corporation 82G33/G31/P35/P31 Express PCI Express Root Port [8086:29c1] (rev 02)
00:1a.0 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 [8086:2937] (rev 02)
00:1a.1 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #5 [8086:2938] (rev 02)
00:1a.7 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #2 [8086:293c] (rev 02)
00:1b.0 Audio device [0403]: Intel Corporation 82801I (ICH9 Family) HD Audio Controller [8086:293e] (rev 02)
00:1c.0 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 1 [8086:2940] (rev 02)
00:1c.2 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 3 [8086:2944] (rev 02)
00:1d.0 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 [8086:2934] (rev 02)
00:1d.1 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 [8086:2935] (rev 02)
00:1d.2 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 [8086:2936] (rev 02)
00:1d.3 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #6 [8086:2939] (rev 02)
00:1d.7 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 [8086:293a] (rev 02)
00:1e.0 PCI bridge [0604]: Intel Corporation 82801 PCI Bridge [8086:244e] (rev 92)
00:1f.0 ISA bridge [0601]: Intel Corporation 82801IR (ICH9R) LPC Interface Controller [8086:2916] (rev 02)
00:1f.2 IDE interface [0101]: Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 4 port SATA Controller [IDE mode] [8086:2920] (rev 02)
00:1f.3 SMBus [0c05]: Intel Corporation 82801I (ICH9 Family) SMBus Controller [8086:2930] (rev 02)
00:1f.5 IDE interface [0101]: Intel Corporation 82801I (ICH9 Family) 2 port SATA Controller [IDE mode] [8086:2926] (rev 02)
02:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 02)
04:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK208B [GeForce GT 710] [10de:128b] (rev a1)
04:00.1 Audio device [0403]: NVIDIA Corporation GK208 HDMI/DP Audio Controller [10de:0e0f] (rev a1)
 
If this definatly doesnt suppost passthrough which i guess g33 chipset doesnt, can someone give me a budget model server that will definatly work with passthrough? Ive been looking on ebay but tbh I dont really know what im looking for. I dont want to splash cash and end up back at square one. Thanks in advance.
I want a server I can pass through gpu and USB.
 
Ive seen this Dell PowerEdge T110 II Server, Xeon E3-1220, 8GB DDR3. No idea if it can support VT-d and passthrough and most of the sellers dont know either unfortunatly.
 
IOMMU group * 00:00.0 Host bridge [0600]: Intel Corporation 82G33/G31/P35/P31 Express DRAM Controller [8086:29c0] (rev 02)
00:01.0 PCI bridge [0604]: Intel Corporation 82G33/G31/P35/P31 Express PCI Express Root Port [8086:29c1] (rev 02)
...
This shows us that it is indeed Intel chipset G33, G31, P35 or P31. All of which do not support VT-d.
 
Is there a motherboard that does support it where i could reuse my socket 775 cpu and ddr2 ram?
Yes, there have been motherboards with a Q35 chipset,

You keep asking about DELL and HP but passthrough is not a business case for them. They are also not clear about which chipsets they use for their custom motherboards and whether their custom BIOS version support passthrough.

No manufacturer explicitly test any parts of the hardware they make for passthrough, it is not a common use case for them. Passthrough is always a trial and error, hit or miss.
Maybe you should search for success stories from other users and buy the exact same system, so you'll know it can work.
Or build your own system using common of-the-shelft parts that you know support passthrough. Either because you can lookup the specifications or because of other people's successes.
Note that you'll have to investigate any hardware part because not all GPUs and USB controller do work with passthrough, even when the CPU and motherboard support it.

Please investigate yourself instead of asking. Lookup the motherboard for a system you could possible buy, find out the chipset, find out whether it supports Intel VT-d or AMD-Vi, find out whether it supports your CPU and memory. I've given you lots of links (the orange texts in my posts) to Wikipedia and Intel to find these thinks out.
 
Ive already been investigating, but being new to this Im still unsure as it seems a bit of a mine field and roll of the dice. I just dont want to throw money away so was hoping someone might chip in with a system they have that works.
 
video=vesafb:off video=efifb:off might be necessary but it is also what will prevent you from seeing boot messages and a host console when things go wrong.
Please don't use pcie_acs_override until you have had a close look at the IOMMU groups.
Blacklisting drivers and interrupt remapping might not even be necessary. iommu=pt has nothing to do with passthrough and nofb nomodeset are also not needed.

I you are still seeing boot messages and a console, then it did not activate. What does cat /proc/cmdline show? Are all BIOS settings about IOMMU and ACS Enabled (not just on Auto)? Are you on the latest BIOS version?

PT Mode​

Both Intel and AMD chips can use the additional parameter iommu=pt, added in the same way as above to the kernel cmdline.

iommu=pt

This enables the IOMMU translation only when necessary, the adapter does not need to use DMA translation to the memory, and can thus improve performance for hypervisor PCIe devices (which are not passthroughed to a VM)
 
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