1U server for 500 bucks

Unreal? Actually, if you assemble yourself and choose the right parts.
And now the slides:

Housing AIC RAC1E-F01 :

The cost of 4000-4500 rubles.

Raiser Card 1x PCI-32 RC1-009E :

The cost of 600-700 rubles.

TTC-NK54TZ fan for 775 socket :

The cost of 370-440 rubles.
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Giga-Byte GA-945GCM-S2L motherboard :

The cost of 930-1200 rubles.

Intel Celeron CPU E1200 TDP 65W processor
The cost of 1200 rubles.

Memory DDR-II 512MB
The cost of 200-300 rubles.

HDD 80Gb
The cost of 1000-1200 rubles.

The cost of the whole set is 8300-9540 rubles. If you take the dollar for 25 rubles, it turns out the cost of 332-381 bucks. If you need a plug on the connectors of the motherboard (the standard plugs that come with the motherboard will have to be cut severely), then you need to add another 500-600 rubles.

The maximum cooler can dissipate 105 watts. The enclosure only comes without a fan. TDP processor used 65 watts. When testing the thermal mode at full load, the margin to the throttling response temperature is 10 degrees.

UPD:
I was asked to write about the tasks. From my point of view, he can perform the following tasks:
1. Firewall, proxy server. The throughput will be on the order of 100-200mbit, maybe more, everything strongly depends on how traffic is processed.
2. IP-PBX (Asterisk). Sul according to estimates from the developers such a piece of iron should pull 30 simultaneous conversations (E1). True, the board will be twice as expensive as the server :)
3. DHCP / DNS server. Here you can put a weaker iron until epia
4. Web server for development.
5. Mail server.

UPD2: A little more explanation for those who are fighting for real servers. This is only about the low-end sector. If you need more reliability or less maintenance problems, buy normal branded servers. It is recommended to collect servers only for those who understand what they are doing and understand why they are doing it.

PS Prices were taken from price.ru so that in reality it could be more expensive.