Is this a good trade: my gaming PC for an iphone 3g?

My gaming PC had an i7 processor, GTX 770 GPU, 120 GB SSD, 2 TB HDD, and Windows 8.1 OS and I traded it to my friend for an iPhone 3g 8 gig version.

Is this a good trade? Both the PC and the phone was used.

No it's not a good trade, the phone is worth a fraction of the PC.

the computers probably worth 15-20 times more than the phone.

No, it will be worst trade ever…

The graphics card in the computer alone is worth more than the phone.
Is it a good trade? Only if you really need an iPhone 3 in less time than you could sell the PC for cash.

Well i7 cores are 200-400 Gtx 770 200-400 SSD 120GB about 100 2TB HDD 100 Windows 8.1 100+ depending what version.
And you forgot ram, cooling, case etc.
So bad trade for a 300-400 phone, with a low memory.
So you lost anywere from 400 to 700 depending on few factors.

Iphone 3g is not enough for your gaming PC, your friend should also sell himself/herself.

Graphics card in the computer

Sorry but your an idiot. A iPhone 3 is worth about $200 which is less than your gpu is worth by itself